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1.
Phys Rev Lett ; 125(15): 153602, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33095609

RESUMO

Hybrid spin-mechanical setups offer a versatile platform for quantum science and technology, but improving the spin-phonon as well as the spin-spin couplings of such systems remains a crucial challenge. Here, we propose and analyze an experimentally feasible and simple method for exponentially enhancing the spin-phonon and the phonon-mediated spin-spin interactions in a hybrid spin-mechanical setup, using only linear resources. Through modulating the spring constant of the mechanical cantilever with a time-dependent pump, we can acquire a tunable and nonlinear (two-phonon) drive to the mechanical mode, thus amplifying the mechanical zero-point fluctuations and directly enhancing the spin-phonon coupling. This method allows the spin-mechanical system to be driven from the weak-coupling regime to the strong-coupling regime, and even the ultrastrong coupling regime. In the dispersive regime, this method gives rise to a large enhancement of the phonon-mediated spin-spin interactions between distant solid-state spins, typically two orders of magnitude larger than that without modulation. As an example, we show that the proposed scheme can apply to generating entangled states of multiple spins with high fidelities even in the presence of large dissipations.

2.
Zhongguo Gu Shang ; 33(3): 230-4, 2020 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-32233249

RESUMO

OBJECTIVE: To explore clinical effect of open reduction and internal fixation through a single lateral approach for Pilon fractures. METHODS: From January 2016 to May 2017, 28 patients with Pilon fractures were treated with open reduction and internal fixation through a single lateral approach. Among them, including 17 males and 11 females, aged from 25 to 59 years old with an average of (39.2±12.2) years old; 13 patients on the left side and 15 patients on the right side; according to Rüedi-Allgöwer classificaton, 7 patients were typeⅠ, 11 patients were typeⅡ, 10 patients were type Ⅲ. All patients were performed external fixation or calcaneal traction within 24 h of emergency, and open reduction and internal fixation was performed after swelling of soft tissue. Healing of incision and fracture, postoperative complications were observed, and AOFAS score at 1 year after operation was used to evaluate ankle joint function. RESULTS: Twenty-eight patients were followed up from 12 to 25 months with an average of (16.4±7.2) months. Two patients occurred superficial wound infection caused delayed wound healing, 1 patient occurred partial skin necrosis and healed after wound dressing change. The healing time of incision ranged from 11 to 25 days with an average of (15.2±8.4) days. All patients got bone union and the time ranged from 12 to 18 weeks with an average of (15.2±3.4) weeks. Two patients suffered from ankle pain after walking postoperatively and X-ray showed traumatic arthritis, the pain got better with the treatment of non steroidal anti inflammatory drugs. No cases of deep infection, nonunion, delayed union, malunion, loosening of internal fixation occurred after operation. AOFAS score at 1 year after operation was 89.6±5.7, 14 patients got excellent results, 12 good, and 2 fair. CONCLUSION: The single lateral approach for surgical treatment of Pilon fractures could provide sufficient exposure, reduction and fixation with less soft tissue application and the clinical curative effect is satisfied. However, for Pilon fracture with varus deformity or comminuted fracture on the medial side of tibial, it is difficult to place the main plate on the medial side of tibial. Instead, anteromedial incision or extensive anterior incision is more suitable.


Assuntos
Fraturas do Tornozelo , Fraturas da Tíbia , Adulto , Feminino , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
3.
Phys Rev Lett ; 120(9): 093601, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29547303

RESUMO

We propose an experimentally feasible method for enhancing the atom-field coupling as well as the ratio between this coupling and dissipation (i.e., cooperativity) in an optical cavity. It exploits optical parametric amplification to exponentially enhance the atom-cavity interaction and, hence, the cooperativity of the system, with the squeezing-induced noise being completely eliminated. Consequently, the atom-cavity system can be driven from the weak-coupling regime to the strong-coupling regime for modest squeezing parameters, and even can achieve an effective cooperativity much larger than 100. Based on this, we further demonstrate the generation of steady-state nearly maximal quantum entanglement. The resulting entanglement infidelity (which quantifies the deviation of the actual state from a maximally entangled state) is exponentially smaller than the lower bound on the infidelities obtained in other dissipative entanglement preparations without applying squeezing. In principle, we can make an arbitrarily small infidelity. Our generic method for enhancing atom-cavity interaction and cooperativities can be implemented in a wide range of physical systems, and it can provide diverse applications for quantum information processing.

4.
Sci Rep ; 7(1): 14116, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-29074851

RESUMO

We propose an efficient scheme for preparing entangled states between two separated nitrogen-vacancy (NV) centers in a spin-mechanical system via a dissipative quantum dynamical process. The proposal actively exploits the nanomechanical resonator (NAMR) damping to drive the NV centers to the target state through a quantum reservoir engineering approach. The distinct features of the present work are that we turn the detrimental source of noise into a resource and only need high-frequency low-Q mechanical resonators, which make our scheme more simple and feasible in experimental implementation. This protocol may have interesting applications in quantum information processing with spin-mechanical systems.

5.
Phys Rev Lett ; 117(1): 015502, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27419577

RESUMO

We show that nitrogen-vacancy (NV) centers in diamond interfaced with a suspended carbon nanotube carrying a dc current can facilitate a spin-nanomechanical hybrid device. We demonstrate that strong magnetomechanical interactions between a single NV spin and the vibrational mode of the suspended nanotube can be engineered and dynamically tuned by external control over the system parameters. This spin-nanomechanical setup with strong, intrinsic, and tunable magnetomechanical couplings allows for the construction of hybrid quantum devices with NV centers and carbon-based nanostructures, as well as phonon-mediated quantum information processing with spin qubits.

6.
Sci Rep ; 6: 19065, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26753744

RESUMO

We investigate the electromechanical coupling between a nanomechanical resonator and two parametrically coupled superconducting coplanar waveguide cavities that are driven by a two-mode squeezed microwave source. We show that, with the selective coupling of the resonator to the cavity Bogoliubov modes, the radiation-pressure type coupling can be greatly enhanced by several orders of magnitude, enabling the single photon strong coupling to be reached. This allows the investigation of a number of interesting phenomena such as photon blockade effects and the generation of nonclassical quantum states with electromechanical systems.

7.
Opt Express ; 19(2): 1207-16, 2011 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-21263662

RESUMO

We develop a one-step scheme for generating multiparticle entangled states between two cold atomic clouds in distant cavities coupled by an optical fiber. We show that, through suitably choosing the intensities and detunings of the fields and precisely tuning the time evolution of the system, multiparticle entanglement between the separated atomic clouds can be engineered deterministically, in which quantum manipulations are insensitive to the states of the cavity and losses of the fiber. The experimental feasibility of this scheme is analyzed based on recent experimental advances in the realization of strong coupling between cold 87Rb clouds and fiber-based cavity. This scheme may open up promising perspectives for implementing quantum communication and networking with coupled cavities connected by optical fibers.


Assuntos
Modelos Teóricos , Fibras Ópticas , Refratometria/instrumentação , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
8.
Yi Chuan ; 25(6): 735-9, 2003 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15639972

RESUMO

Single nucleotide polymorphism(SNP) is the most common type of sequence difference between alleles, which can be used as a kind of high-throughput genetic marker. Several different routes have been developed to discover and identify SNP. These include the direct sequencing of PCR amplicons, electronic SNP(eSNP) and so on. SNP assays have been made in many crop species such as maize and soybean. The elite germplasm of some crops have been narrowed in genetic diversity, increasing the amount of linkage disequilibrium (LD) present and facilitating the association of SNP haplotypes at candidate gene loci with phenotypes. SNP analysis has been broadly used in the field of plant gene mapping, integration of genetic and physical maps, DNA marker-assisted breeding and functional genomics.

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