An integrated microwave-to-optics interface for scalable quantum computing.

Microwave-to-optics transduction is emerging as a vital technology for scaling quantum computers and quantum networks. To establish useful entanglement links between qubit processing units, several key conditions must be simultaneously met: the transducer must add less than a single quantum of input-referred noise and operate with high efficiency, as well as large bandwidth and high repetition rate. Here we present a design for an integrated transducer based on a planar superconducting resonator coupled to a silicon photonic cavity through a mechanical oscillator made of lithium niobate on silicon. We experimentally demonstrate its performance with a transduction efficiency of 0.9% with 1 µW of continuous optical power and a spectral bandwidth of 14.8 MHz. With short optical pulses, we measure the added noise that is limited to a few photons, with a repetition rate of up to 100 kHz. Our device directly couples to a 50 Ω transmission line and can be scaled to a large number of transducers on a single chip, laying the foundations for distributed quantum computing.

Syntheses and crystal structures of a nitro-anthracene-isoxazole and its oxidation product.

The syntheses and structures of an unexpected by-product from an iodination reaction, namely, ethyl 5-methyl-3-(10-nitro-anthracen-9-yl)isoxazole-4-carb-oxy-l-ate, C21H16N2O5, (I), and its oxidation product, ethyl 3-(9-hy-droxy-10-oxo-9,10-di-hydro-anthracen-9-yl)-5-methyl-isoxazole-4-carboxyl-ate, C21H17NO5 (V) are described. Compound (I) crystallizes with two mol-ecules in the asymmetric unit in which the dihedral angles between the anthracene fused-ring systems and isoxazole ring mean planes are 88.67 (16) and 85.64 (16)°; both mol-ecules feature a disordered nitro group. In (V), which crystallizes with one mol-ecule in the asymmetric unit, the equivalent dihedral angle between the almost planar anthrone ring system (r.m.s. deviation = 0.029 Å) and the pendant isoxazole ring is 89.65 (5)°. In the crystal of (I), the mol-ecules are linked by weak C-H⋯O inter-actions into a three-dimensional network and in the extended structure of (V), inversion dimers linked by pairwise O-H⋯O hydrogen bonds generate R 2 2(14) loops.

10-Alkoxy-anthracenyl-isoxazole analogs have sub-micromolar activity against a Glioblastoma multiforme cell line.

A series of 10-alkoxy-Anthryl-isoxazole-pyrrole-doubletails (RO-AIMs) were synthesized using a crown ether assisted nucleophilic aromatic substitution followed by a modified Schotten-Baumann reaction. The novel RO-AIMs described here exhibit robust growth inhibition for the human SNB19 CNS glioblastoma cell line, and biphenyl analog 8c had activity in the nanomolar regime, which represents the most efficacious compound in the AIM series to date. Computational modeling for RO-AIMs binding in a ternary complex with c-myc quadruplex DNA and its helicase DHX36 is presented which represents our current working hypothesis.

10-N-heterocylic aryl-isoxazole-amides (AIMs) have robust anti-tumor activity against breast and brain cancer cell lines and useful fluorescence properties.

A novel series of anthracenyl-isoxazole amide (AIM) antitumor agents containing N-heterocycles in the 10 position (N-het) were synthesized using palladium cross-coupling. The unique steric environment of the N-het-AIMs required individual optimization in each case. Lanthanide mediated double activation was used to couple the dimethylamino pyrrole moiety, required for antitumor action. Robust antitumor activity was observed against breast and brain cancer cell lines. The compounds were docked with the c-myc oncogene promoter sequence, which adopts a G4 quadruplex DNA conformation, and represents the working hypothesis for biological action. The N-het-AIMs have useful fluorescence properties, allowing for observation of their distribution within tumor cells.

Ethyl 5-methyl-3-[11-(pyridin-2-yl)-6,11-di-hydro-6,11-ep-oxy-dibenzo[b,e]oxepin-6-yl]isoxazole-4-carboxylate: a bicyclic acetal from the rearrangement of an anthracenyl isoxazole.

The title compound, C26H20N2O5, is a rearrangement product of an o-pyridinyl anthracenyl isoxazole ester. It features a bicyclic acetal structure, which has two extended almost co-planar ring systems, which subtend a fold angle of 102.17 (5)°. In the crystal, the mol-ecules are closely knitted together through C-H⋯N and C-H⋯O hydrogen bonds and form chains of alternating enanti-omers propagating along the c-axis direction.

Coherent optomechanical state transfer between disparate mechanical resonators.

Systems of coupled mechanical resonators are useful for quantum information processing and fundamental tests of physics. Direct coupling is only possible with resonators of very similar frequency, but by using an intermediary optical mode, non-degenerate modes can interact and be independently controlled in a single optical cavity. Here we demonstrate coherent optomechanical state swapping between two spatially and frequency separated resonators with a mass ratio of 4. We find that, by using two laser beams far detuned from an optical cavity resonance, efficient state transfer is possible. Although the demonstration is classical, the same technique can be used to generate entanglement between oscillators in the quantum regime.Coupled mechanical resonators where each mode can be separately controlled are a promising system for quantum information processing. Here, Weaver et al. demonstrate coherent swapping of optomechanical states between two separate resonators.

AIMing towards improved antitumor efficacy.

Using the structure-activity relationship emerging from previous Letter, and guided by pharmacokinetic properties, new AIMs have been prepared with both improved efficacy against human glioblastoma cells and cell permeability as determined by fluorescent confocal microscopy. We present our first unambiguous evidence for telomeric G4-forming oligonucleotide anisotropy by NMR resulting from direct interaction with AIMs, which is consistent with both our G4 melting studies by CD, and our working hypothesis. Finally, we show that AIMs induce apoptosis in SNB-19 cells.

Ethyl 3-(10-bromo-anthracen-9-yl)-5-methyl-1,2-oxazole-4-carboxyl-ate.

In the title compound, C21H16BrNO3, the mean planes of the anthracene tricycle and isoxazole ring are inclined to each other at a dihedral angle of 72.12 (7)°. The carb-oxy group is slightly out of the isoxazole mean plane, with a maximum deviation of 0.070 (5) Šfor the carbonyl O atom. In the crystal, pairs of weak C-H⋯O hydrogen bonds link the mol-ecules into dimers, and weak C-H⋯N inter-actions further link these dimers into corrugated layers parallel to the bc plane.

Improved synthesis of 3-aryl isoxazoles containing fused aromatic rings.

A critical comparison of methods to prepare sterically hindered 3-aryl isoxazoles containing fused aromatic rings using the nitrile oxide cycloaddition (NOC) reveal that modification of the method of Bode, Hachisu, Matsuura, and Suzuki (BHMS), utilizing either triethylamine as base or sodium enolates of the diketone, ketoester, and ketoamide dipolarophiles, respectively, was the method of choice for this transformation.