Quasiparticle Poisoning of Superconducting Qubits from Resonant Absorption of Pair-Breaking Photons.

The ideal superconductor provides a pristine environment for the delicate states of a quantum computer: because there is an energy gap to excitations, there are no spurious modes with which the qubits can interact, causing irreversible decay of the quantum state. As a practical matter, however, there exists a high density of excitations out of the superconducting ground state even at ultralow temperature; these are known as quasiparticles. Observed quasiparticle densities are of order 1  μm^{-3}, tens of orders of magnitude greater than the equilibrium density expected from theory.

Hardware Implementation of Quantum Stabilizers in Superconducting Circuits.

Stabilizer operations are at the heart of quantum error correction and are typically implemented in software-controlled entangling gates and measurements of groups of qubits. Alternatively, qubits can be designed so that the Hamiltonian corresponds directly to a stabilizer for protecting quantum information. We demonstrate such a hardware implementation of stabilizers in a superconducting circuit composed of chains of π-periodic Josephson elements.

Ionic liquid-mediated bis[(3-methyldimethoxysilyl)propyl] polypropylene oxide-based polar sol-gel coatings for capillary microextraction.

Two ionic liquids (IL), namely, 1-methyl-3-octylimidazolium chloride (MOIC) and trihexyltetradecylphosphonium tetrafluoroborate (TTPT) were used to prepare polar and nonpolar sol-gel coatings for capillary microextraction (CME). Bis[(3-methyldimethoxysilyl)propyl] polypropylene oxide (BMPO), containing sol-gel active terminal methoxysilyl groups and polar propylene oxide repeating units, was used to prepare polar sol-gel hybrid organic-inorganic coatings. Hydroxy-terminated poly(dimethyl-co-diphenylsiloxane) was used as the sol-gel active organic component for nonpolar sol-gel hybrid coatings.

Ionic liquid-mediated sol-gel coatings for capillary microextraction.

Ionic liquid (IL)-mediated sol-gel hybrid organic-inorganic materials present enormous potential for effective use in analytical microextraction. This opportunity, however, has not yet been explored. One obstacle to materializing this prospect arises from high viscosity of ILs significantly slowing down sol-gel reactions.

Sol-gel immobilized short-chain poly(ethylene glycol) coating for capillary microextraction of underivatized polar analytes.

Sol-gel coating with covalently bonded low-molecular-weight (MW<300 Da) poly(ethylene glycol) (PEG) chains was developed for capillary microextraction (CME). The sol-gel chemistry proved effective in the immobilization of low-molecular-weight PEGs thanks to the formation of chemical bonds between the organic-inorganic hybrid sol-gel PEG coating and the fused silica capillary inner surface. This chemical anchorage provided excellent thermal and solvent stability to the created sol-gel PEG coating as is evidenced by its high upper limit of allowable conditioning temperature (340 degrees C) and its practically identical performance before and after rinsing with various solvents.