Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.429
Filtrar
1.
Biochemistry ; 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35723977

RESUMO

Recent studies have shown that Escherichia coli often carries a biosynthetic gene cluster termed either the pks island or the clb cluster that allows the production of a genotoxic polyketide-nonribosomal peptide hybrid secondary metabolite called colibactin. While the gene cluster is not always expressed, when the strain that resides in the colon produces the genotoxin, it is suspected to become a risk factor for colorectal cancer. Therefore, there is great interest in devising a simple method for the detection of colibactin-producing strains and understanding the detailed mechanism of how colibactin can induce oncogenesis, to develop convenient early screening methods and possible preventive treatments against colorectal cancer. However, the definitive chemical structure of colibactin remained elusive until recently, primarily due to its low yield and instability. In this review, we will briefly trace the recent studies leading to the identification of the structure of the active intact colibactin. Subsequently, we will describe our efforts toward developing simple methods for detecting colibactin producers, where we established methods based on the conventional polymerase chain reaction and loop-mediated isothermal amplification techniques. We also designed an activity-based fluorogenic probe for detecting colibactin-producing strains that could discern colibactin production levels among the E. coli strains screened. Using the probe, we isolated a wild-type high-colibactin-producing strain from a colorectal cancer tissue sample that proved to be valuable in identifying new colibactin metabolites and structurally characterizing them by nuclear magnetic resonance. Those techniques and the chemical insight they furnished should improve the fight against colorectal cancer.

2.
Nat Commun ; 13(1): 3461, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710635

RESUMO

The kagome lattice provides a fertile platform to explore novel symmetry-breaking states. Charge-density wave (CDW) instabilities have been recently discovered in a new kagome metal family, commonly considered to arise from Fermi-surface instabilities. Here we report the observation of Raman-active CDW amplitude modes in CsV3Sb5, which are collective excitations typically thought to emerge out of frozen soft phonons, although phonon softening is elusive experimentally. The amplitude modes strongly hybridize with other superlattice modes, imparting them with clear temperature-dependent frequency shift and broadening, rarely seen in other known CDW materials. Both the mode mixing and the large amplitude mode frequencies suggest that the CDW exhibits the character of strong electron-phonon coupling, a regime in which phonon softening can cease to exist. Our work highlights the importance of the lattice degree of freedom in the CDW formation and points to the complex nature of the mechanism.

3.
Nano Lett ; 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35714056

RESUMO

Recently, exciton-polaritons in lead halide perovskite microcavities have been extensively investigated to address striking phenomena such as polariton condensation and quantum emulation. However, a critical step in advancing these findings into practical applications, i.e., realizing electrically pumped perovskite polariton light-emitting devices, has not yet been presented. Here, we devise a new method to combine the device with a microcavity and report the first halide perovskite polariton light-emitting device. Specifically, the device is based on a CsPbBr3 capacitive structure, which can inject the electrons and holes from the same electrode, conducive to the formation of excitons and simultaneously maintaining the high quality of the microcavity. In addition, highly polarized polariton emissions have been demonstrated due to the optical birefringence in the CsPbBr3 microplate. This work paves the way for realizing practical polaritonic devices such as high-speed light-emitting devices for information communications and inversionless electrically pumped lasers based on perovskites.

4.
Nat Commun ; 13(1): 3431, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701395

RESUMO

Techniques to mold the flow of light on subwavelength scales enable fundamentally new optical systems and device applications. The realization of programmable, active optical systems with fast, tunable components is among the outstanding challenges in the field. Here, we experimentally demonstrate a few-pixel beam steering device based on electrostatic gate control of excitons in an atomically thin semiconductor with strong light-matter interactions. By combining the high reflectivity of a MoSe2 monolayer with a graphene split-gate geometry, we shape the wavefront phase profile to achieve continuously tunable beam deflection with a range of 10°, two-dimensional beam steering, and switching times down to 1.6 nanoseconds. Our approach opens the door for a new class of atomically thin optical systems, such as rapidly switchable beam arrays and quantum metasurfaces operating at their fundamental thickness limit.

5.
J Dermatol Sci ; 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35717315

RESUMO

BACKGROUND: The biological functions of Hyaluronic acid are related to its molecular weight and binding to its receptor, Toll-like receptor4 (TLR4) or CD44. Recent studies have shown that low-molecular-weight Hyaluronic acid (LMW-HA) exhibits proinflammatory effects, while high-molecular-weight Hyaluronic acid (HMW-HA) functions as an anti-inflammatory factor. UVB-induced epidermal inflammation is mainly mediated by endogenous molecules, such as damage-associated molecular patterns (DAMPs), that cause severe skin damage by activating TLR signaling pathways. OBJECTIVE: Since both LMW- and HMW-HA have inhibitory functions on TLR-mediated macrophage inflammation, HA is assumed to suppress UVB-induced DAMP-mediated inflammation in the skin. In this study, both Ultra- low-molecular-weight Hyaluronic acid (uLMW-HA) and HMW-HA were found to inhibit UVB-induced keratinocyte inflammation. METHODS: HaCaT cells were treated with medium containing Hyaluronic acid at the appropriate concentration after 15 mJ/cm2 irradiation. Secreted protein levels were determined with ELISA kits. Expression levels of proteins downstream of TLR4 were detected by Simple Western system. RESULTS: By competitively binding to TLR4, uLMW-HA downregulated Calprotectin-induced TRAF6 expression, which might be the direct process by which uLMW-HA decreased UVB-induced IL-6 secretion. Reduced CD44 variant (CD44v) expression in keratinocytes attenuated the inhibitory effect of both uLMW-HA and HMW-HA on UVB-induced inflammation, which indicated the involvement of CD44v in HA-regulated anti-inflammatory activity. CONCLUSION: Overall, this research indicates that Hyaluronic acid is more than a moisturizer; it is also a biologically effective material that can prevent the excessive skin inflammation caused in daily life, especially in the late stages after sunburn.

6.
Phys Rev Lett ; 128(23): 237403, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35749182

RESUMO

Atomically thin semiconductors can be readily integrated into a wide range of nanophotonic architectures for applications in quantum photonics and novel optoelectronic devices. We report the observation of nonlocal interactions of "free" trions in pristine hBN/MoS_{2}/hBN heterostructures coupled to single mode (Q>10^{4}) quasi 0D nanocavities. The high excitonic and photonic quality of the interaction system stems from our integrated nanofabrication approach simultaneously with the hBN encapsulation and the maximized local cavity field amplitude within the MoS_{2} monolayer. We observe a nonmonotonic temperature dependence of the cavity-trion interaction strength, consistent with the nonlocal light-matter interactions in which the extent of the center-of-mass (c.m.) wave function is comparable to the cavity mode volume in space. Our approach can be generalized to other optically active 2D materials, opening the way toward harnessing novel light-matter interaction regimes for applications in quantum photonics.

7.
Sci Rep ; 12(1): 10936, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35768480

RESUMO

We present a dry pick-and-flip assembly technique for angle-resolved photoemission spectroscopy (ARPES) of van der Waals heterostructures. By combining Elvacite2552C acrylic resin and 1-ethyl-3-methylimidazolium ionic liquid, we prepared polymers with glass transition temperatures (Tg) ranging from 37 to 100 â„ƒ. The adhesion of the polymer to the 2D crystals was enhanced at [Formula: see text]. By utilizing the difference in [Formula: see text], a 2D heterostructure can be transferred from a high-[Formula: see text] polymer to a lower-[Formula: see text] polymer, which enables flipping its surface upside down. This process is suitable for assembling heterostructures for ARPES, where the top capping layer should be monolayer graphene. The laser-based micro-focused ARPES measurements of 5-layer WTe2, 3-layer MoTe2, 2-layer WTe2/few-layer Cr2Ge2Te6, and twisted double bilayer WTe2 demonstrate that this process can be utilized as a versatile sample fabrication method for investigating the energy spectra of 2D heterostructures.

8.
Nat Mater ; 21(7): 748-753, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35710632

RESUMO

One-dimensional electron systems exhibit fundamentally different properties than higher-dimensional systems. For example, electron-electron interactions in one-dimensional electron systems have been predicted to induce Tomonaga-Luttinger liquid behaviour. Naturally occurring grain boundaries in single-layer transition metal dichalcogenides exhibit one-dimensional conducting channels that have been proposed to host Tomonaga-Luttinger liquids, but charge density wave physics has also been suggested to explain their behaviour. Clear identification of the electronic ground state of this system has been hampered by an inability to electrostatically gate such boundaries and tune their charge carrier concentration. Here we present a scanning tunnelling microscopy and spectroscopy study of gate-tunable mirror twin boundaries in single-layer 1H-MoSe2 devices. Gating enables scanning tunnelling microscopy and spectroscopy for different mirror twin boundary electron densities, thus allowing precise characterization of electron-electron interaction effects. Visualization of the resulting mirror twin boundary electronic structure allows unambiguous identification of collective density wave excitations having two velocities, in quantitative agreement with the spin-charge separation predicted by finite-length Tomonaga-Luttinger liquid theory.

9.
Nat Commun ; 13(1): 3292, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672329

RESUMO

New phase of matter usually emerges when a given symmetry breaks spontaneously, which can involve charge, spin, and valley degree of freedoms. Here, we report an observation of new correlated insulators evolved from spin-polarized states to valley-polarized states in twisted double bilayer graphene (TDBG) driven by the displacement field (D). At a high field |D | > 0.7 V/nm, we observe valley polarized correlated insulators with a big Zeeman g factor of ~10, both at v = 2 in the moiré conduction band and more surprisingly at v = -2 in the moiré valence band. Moreover, we observe a valley polarized Chern insulator with C = 2 emanating at v = 2 in the electron side and a valley polarized Fermi surface around v = -2 in the hole side. Our results demonstrate a feasible way to realize isospin control and to obtain new phases of matter in TDBG by the displacement field, and might benefit other twisted or non-twisted multilayer systems.

10.
Nano Lett ; 22(12): 4949-4955, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35649273

RESUMO

We present inverted spin-valve devices fabricated from chemical vapor deposition (CVD)-grown bilayer graphene (BLG) that show more than a doubling in device performance at room temperature compared to state-of-the-art bilayer graphene spin valves. This is made possible by a polydimethylsiloxane droplet-assisted full-dry transfer technique that compensates for previous process drawbacks in device fabrication. Gate dependent Hanle measurements reveal spin lifetimes of up to 5.8 ns and a spin diffusion length of up to 26 µm at room temperature combined with a charge carrier mobility of about 24 000 cm2(V s)-1 for the best device. Our results demonstrate that CVD-grown BLG shows equally good room temperature spin transport properties as both CVD-grown single-layer graphene and even exfoliated single-layer graphene.

11.
Nano Lett ; 22(12): 4640-4645, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35658492

RESUMO

We demonstrate van der Waals double quantum well (vDQW) devices based on few-layer WSe2 quantum wells and a few-layer h-BN tunnel barrier. Due to the strong out-of-plane confinement, an exfoliated WSe2 exhibits quantized subband states at the Γ point in its valence band. Here, we report resonant tunneling and negative differential resistance in vDQW at room temperature owing to momentum- and energy-conserved tunneling between the quantized subbands in each well. Compared to single quantum well (QW) devices with only one QW layer possessing quantized subbands, superior current peak-to-valley ratios were obtained for the DQWs. Our findings suggest a new direction for utilizing few-layer-thick transition metal dichalcogenides in subband QW devices, bridging the gap between two-dimensional materials and state-of-the-art semiconductor QW electronics.

12.
Nature ; 606(7914): 494-500, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35705819

RESUMO

Magic-angle twisted trilayer graphene (MATTG) has emerged as a moiré material that exhibits strong electronic correlations and unconventional superconductivity1,2. However, local spectroscopic studies of this system are still lacking. Here we perform high-resolution scanning tunnelling microscopy and spectroscopy of MATTG that reveal extensive regions of atomic reconstruction favouring mirror-symmetric stacking. In these regions, we observe symmetry-breaking electronic transitions and doping-dependent band-structure deformations similar to those in magic-angle bilayers, as expected theoretically given the commonality of flat bands3,4. Most notably in a density window spanning two to three holes per moiré unit cell, the spectroscopic signatures of superconductivity are manifest as pronounced dips in the tunnelling conductance at the Fermi level accompanied by coherence peaks that become gradually suppressed at elevated temperatures and magnetic fields. The observed evolution of the conductance with doping is consistent with a gate-tunable transition from a gapped superconductor to a nodal superconductor, which is theoretically compatible with a sharp transition from a Bardeen-Cooper-Schrieffer superconductor to a Bose-Einstein-condensation superconductor with a nodal order parameter. Within this doping window, we also detect peak-dip-hump structures that suggest that superconductivity is driven by strong coupling to bosonic modes of MATTG. Our results will enable further understanding of superconductivity and correlated states in graphene-based moiré structures beyond twisted bilayers5.

13.
J Am Chem Soc ; 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732002

RESUMO

Two-dimensional (2D) magnetic crystals hold promise for miniaturized and ultralow power electronic devices that exploit spin manipulation. In these materials, large, controllable magnetocrystalline anisotropy (MCA) is a prerequisite for the stabilization and manipulation of long-range magnetic order. In known 2D magnetic crystals, relatively weak MCA typically results in soft ferromagnetism. Here, we demonstrate that ferromagnetic order persists down to the thinnest limit of FexTaS2 (Fe-intercalated bilayer 2H-TaS2) with giant coercivities up to 3 T. We prepare Fe-intercalated TaS2 by chemical intercalation of van der Waals-layered 2H-TaS2 crystals and perform variable-temperature transport, transmission electron microscopy, and confocal Raman spectroscopy measurements to shed new light on the coupled effects of dimensionality, degree of intercalation, and intercalant order/disorder on the hard ferromagnetic behavior of FexTaS2. More generally, we show that chemical intercalation gives access to a rich synthetic parameter space for low-dimensional magnets, in which magnetic properties can be tailored by the choice of the host material and intercalant identity/amount, in addition to the manifold distinctive degrees of freedom available in atomically thin, van der Waals crystals.

14.
Nano Lett ; 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35736540

RESUMO

Proximity-induced superconductivity in a ferromagnet can induce Cooper pairs with a finite center-of-mass momentum and stabilize Josephson junctions (JJs) with π phase difference in superconductor-ferromagnet-superconductor heterostructures. The emergence of two-dimensional layered superconducting and magnetic materials promises a new platform for realizing π JJs with atomically sharp interfaces. Here we demonstrate a thickness-driven 0-π transition in JJs made of NbSe2 (an Ising superconductor) and Cr2Ge2Te6 (a ferromagnetic semiconductor). By systematically increasing the Cr2Ge2Te6 weak link thickness, we observe a vanishing supercurrent at a critical thickness of ∼8 nm, followed by a re-entrant supercurrent. Near the critical thickness, we further observe unusual supercurrent interference patterns with vanishing critical current around zero in-plane magnetic field. They signify the formation of 0-π JJs (with both 0 and π regions), likely induced by the nanoscale magnetic domains in Cr2Ge2Te6.

15.
Phys Rev Lett ; 128(21): 217701, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35687461

RESUMO

The discovery of flat bands with nontrivial band topology in magic-angle twisted bilayer graphene (MATBG) has provided a unique platform to study strongly correlated phenomena including superconductivity, correlated insulators, Chern insulators, and magnetism. A fundamental feature of the MATBG, so far unexplored, is its high magnetic field Hofstadter spectrum. Here, we report on a detailed magnetotransport study of a MATBG device in external magnetic fields of up to B=31 T, corresponding to one magnetic flux quantum per moiré unit cell Φ_{0}. At Φ_{0}, we observe reentrant correlated insulators at a flat band filling factors of ν=+2 and of ν=+3, and interaction-driven Fermi-surface reconstructions at other fillings, which are identified by new sets of Landau levels originating from these. These experimental observations are supplemented by theoretical work that predicts a new set of eight well-isolated flat bands at Φ_{0}, of comparable band width, but with different topology than in zero field. Overall, our magnetotransport data reveal a qualitatively new Hofstadter spectrum in MATBG, which arises due to the strong electronic correlations in the reentrant flat bands.

16.
Small ; : e2200882, 2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35719033

RESUMO

Two-dimensional (2D) devices and their van der Waals (vdW) heterostructures attract considerable attention owing to their potential for next-generation logic and memory applications. In addition, 2D devices are projected to have high integration capabilities, while maintaining nanoscale thickness. However, the fabrication of 2D devices and their circuits is challenging because of the high precision required to etch and pattern ultrathin 2D materials for integration. Here, the fabrication of a graphene via contact architecture to electrically connect graphene electrodes (or leads) embedded in vdW heterostructures is demonstrated. Graphene via contacts comprising of edge and fluorinated graphene (FG) electrodes are fabricated by successive fluorination and plasma etching processes. A one-step fabrication process that utilizes the graphene contacts is developed for a vertically integrated complementary inverter based on n- and p-type 2D field-effect transistors (FETs). This study provides a promising method to fabricate vertically integrated 2D devices, which are essential in 2D material-based devices and circuits.

17.
Therap Adv Gastroenterol ; 15: 17562848221095372, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35721839

RESUMO

Introduction: The patient-physician relationship is important in implementing appropriate management strategies. The Ulcerative Colitis (UC) Narrative Global Surveys examined patient and physician views on multiple aspects of living with UC. However, there are many other important undiscovered aspects of UC to consider for patients in Japan. Aim: The aim of these ad hoc analyses was to identify detailed practical issues for further optimal care. Methods: Patient and physician questionnaires covered broad aspects of living with UC and practical care. Results were compared to identify gaps. We conducted multifaceted ad hoc analyses on the responses from Japan. Results: In Japan, 210 patients with UC and 151 physicians were surveyed. Most (64%) patients felt they would be more successful if they did not have UC. Physicians were more likely to discuss treatment-related topics, including side effects as a proxy for medication satisfaction, than quality of life-related topics. Physicians underestimated the importance to patients of toileting accidents (28% vs 54%) and overestimated the importance of mucosal healing (59% vs 29%). Although 72% of patients felt comfortable raising concerns with their physician, 53% worried about asking too many questions, as they thought they would be seen as a difficult patient, and 66% wished they had talked more about medication fears. The majority (83%) of patients said they were honest with their physician when discussing their experiences with UC, although 45% regretted not telling them more. Some (26%) patients believed, and some (20%) were not sure, that if their symptoms were under control then their UC was not active. More positively, 65% of patients agreed that UC had made them more appreciative of the important things in life. Conclusion: This survey revealed notable gaps between patients' and physicians' perspectives. Consequently, the importance of patient-physician communication remains constant, even in the era of biologics and treat-to-target strategies. Plain Language Summary: Overlap and differences in views around communication and management of ulcerative colitis between patients and doctors It is important to discover the different ways that ulcerative colitis (UC) can impact individual patients, and to identify differences in views between people with UC and the doctors treating them, to improve patient care. The UC Narrative is a global survey (containing two questionnaires, one for patients, and one for doctors) that gathers information on how UC impacts patients. The survey aims to identify differences between patients' and doctors' views on communication and disease management.In this analysis, we report the results from 210 patients with UC and 151 doctors who completed the UC Narrative survey in Japan, between November 2017 and January 2018. Most patients (85%) were satisfied with their communication with their doctor. However, doctors underestimated patient satisfaction, as they believed that about 71% of their patients were satisfied with communication. Around two-thirds of patients (65%), and most doctors (82%), wanted more discussion about goals for managing or treating UC. Most patients (83%) said they were honest with their doctor when discussing their experiences with UC, although almost half of patients (45%) said they regretted not telling their doctor more. Three-quarters of doctors (75%) felt that their patients were honest with them. Doctors underestimated the importance of toileting accidents to patients and thought that healing the patients' intestine would be more important to the patients than toileting accidents. Some patients had misconceptions about treatment. For example, only 69% of patients knew that it was not OK to stop taking their UC medications once they felt better. This survey shows that even though treatment options for UC have developed, sufficient communication between patients and doctors is very important for overall patient care.

18.
ACS Nano ; 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35679485

RESUMO

Moiré superlattice (mSL)-induced sub-bands in twisted van der Waals homo- and heterostructures govern their optical and electrical properties, rendering additional degrees of freedom such as twist angle. Here, we demonstrate the moiré superlattice effects on the intralayer excitons and trions in a twisted bilayer of MoS2 of H-type stacking at marginal twist angles. We identify the emissions from localized and delocalized sub-bands of intralayer moiré excitons and show their electrical modulation by the corresponding trion formation. The electrical control of the oscillator strength of the moiré excitons also results in the strong tunability of resonant Raman scattering. We find that the gate-induced doping significantly modulates the electronic moiré potential; however, leaves the excitonic moiré confinement unaltered. This effect, coupled with variable moiré trap filling by tuning the optical excitation density, allows us to delineate the different phases of localized and delocalized moiré trions. We demonstrate that the moiré excitons exhibit strong valley coherence that changes in a striking nonmonotonic W-shape with gating due to motional narrowing. These observations from the simultaneous electrostatic control of quasiparticle-dependent moiré potential will lead to exciting effects of tunable many-body phenomena in moiré superlattices.

19.
Complement Med Res ; 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35550377

RESUMO

BACKGROUND: We aimed to explore standardized scales and serum biomarkers for tracking changes in the symptoms and severity of pruritus due to eczema in patients treated with Kampo formulas. PATIENTS AND METHODS: This prospective, single-arm, pre-post comparison case series recruited patients with pruritus mostly due to eczema who consulted the Kampo Clinic at the Keio University Hospital from June 2019 to March 2020. The participants were prescribed a personalized Kampo formula for 12 weeks. Patient profiles and symptoms were assessed every four weeks using the visual analog scale (VAS), patient-oriented eczema measure (POEM) scale, 5-D itch scale (5D), Skindex-16, and eczema area and severity index (EASI). Blood biomarkers and intestinal permeability indicators were measured at the first consultation and 12 weeks later. RESULTS: Pruritus and eczema severity improved significantly over time. The VAS, POEM, 5D, and Skindex-16 scores were well-correlated. The serum interleukin-31 levels decreased significantly after a 12-week intervention. Changes in the interleukin-31 level correlated with the diamine oxidase level at week 0, suggesting the involvement of the Th2 immune system and intestinal permeability in the mechanism of Kampo formulas. CONCLUSION: The evaluated scales are suitable for evaluating subjective symptoms and eczema severity after Kampo treatment; further studies are required to verify study findings.

20.
Nat Commun ; 13(1): 2856, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606355

RESUMO

Electrons exposed to a two-dimensional (2D) periodic potential and a uniform, perpendicular magnetic field exhibit a fractal, self-similar energy spectrum known as the Hofstadter butterfly. Recently, related high-temperature quantum oscillations (Brown-Zak oscillations) were discovered in graphene moiré systems, whose origin lies in the repetitive occurrence of extended minibands/magnetic Bloch states at rational fractions of magnetic flux per unit cell giving rise to an increase in band conductivity. In this work, we report on the experimental observation of band conductivity oscillations in an electrostatically defined and gate-tunable graphene superlattice, which are governed both by the internal structure of the Hofstadter butterfly (Brown-Zak oscillations) and by a commensurability relation between the cyclotron radius of electrons and the superlattice period (Weiss oscillations). We obtain a complete, unified description of band conductivity oscillations in two-dimensional superlattices, yielding a detailed match between theory and experiment.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...