714 research outputs found
Realization of a classical counterpart of a scalable design for adiabatic quantum computation
We implement a classical counterpart of a scalable design for adiabatic
quantum computation. The key element of this design is a coupler providing
controllable coupling between two bistable elements (in our case
superconducting rings with a single Josephson junction playing the role of a
classical counterpart of superconducting flux qubits) The coupler is also a
superconducting ring with a single Josephson junction that operates in the
non-hysteretic mode. The flux coupling between two bistable rings can be
controlled by changing the magnetic flux through the coupler. Thereby, the
coupling can be tuned from ferromagnetic trough zero to to anti-ferromagnetic.Comment: 3 pages, 3 figures v2: extended discussion experimental result
Direct Josephson coupling between superconducting flux qubits
We have demonstrated strong antiferromagnetic coupling between two
three-junction flux qubits based on a shared Josephson junction, and therefore
not limited by the small inductances of the qubit loops. The coupling sign and
magnitude were measured by coupling the system to a high-quality
superconducting tank circuit. Design modifications allowing to continuously
tune the coupling strength and/or make the coupling ferromagnetic are
discussed.Comment: REVTeX 4, 4 pages, 5 figures; v2: completely rewritten, added
finite-temperature results and proposals for ferromagnetic galvanic couplin
Weak continuous monitoring of a flux qubit using coplanar waveguide resonator
We study a flux qubit in a coplanar waveguide resonator by measuring
transmission through the system. In our system with the flux qubit decoupled
galvanically from the resonator, the intermediate coupling regime is achieved.
In this regime dispersive readout is possible with weak backaction on the
qubit. The detailed theoretical analysis and simulations give a good agreement
with the experimental data and allow to make the qubit characterization.Comment: 4 pages, 3 figures, to be published in Phys. Rev.
Four-qubit device with mixed couplings
We present the first experimental results on a device with more than two
superconducting qubits. The circuit consists of four three-junction flux
qubits, with simultaneous ferro- and antiferromagnetic coupling implemented
using shared Josephson junctions. Its response, which is dominated by the
ground state, is characterized using low-frequency impedance measurement with a
superconducting tank circuit coupled to the qubits. The results are found to be
in excellent agreement with the quantum-mechanical predictions.Comment: REVTeX 4, 5pp., 7 EPS figure files. N.B.: "Alec" is my first, and
"Maassen van den Brink" my family name. v2: final published version, with
changed title, different sample micrograph, and several clarification
ΠΠΈΠ½Π΅ΡΠ°Π»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ Π² ΠΏΠ΅ΡΠ΅ΡΠ½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠ΅ Π‘Π½Π΅ΠΆΠ½Π°Ρ-ΠΠ΅ΠΆΠ΅Π½Π½ΠΎΠ³ΠΎ-ΠΠ»Π»ΡΠ·ΠΈΡ (ΠΠ°ΠΏΠ°Π΄Π½ΡΠΉ ΠΠ°Π²ΠΊΠ°Π·, ΠΠ·ΡΠ±ΡΠΊΠΈΠΉ Ρ ΡΠ΅Π±Π΅Ρ): ΠΏΡΠ΅Π΄Π²Π°ΡΠΈΡΠ΅Π»ΡΠ½ΡΠ΅ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΈ Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΈΡ Π΄Π°Π»ΡΠ½Π΅ΠΉΡΠΈΡ ΡΠ°Π±ΠΎΡ
Π ΡΡΠ°ΡΡΠ΅ ΠΏΡΠΈΠ²ΠΎΠ΄ΡΡΡΡ ΡΠ²Π΅Π΄Π΅Π½ΠΈΡ ΠΎ ΠΌΠΈΠ½Π΅ΡΠ°Π»ΡΠ½ΠΎΠΌ ΡΠΎΡΡΠ°Π²Π΅ Π²ΠΎΠ΄Π½ΡΡ
Ρ
Π΅ΠΌΠΎΠ³Π΅Π½Π½ΡΡ
ΠΈ Π²ΠΎΠ΄Π½ΡΡ
ΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΎΡΠ»ΠΎΠΆΠ΅Π½ΠΈΠΉ Π² ΠΏΠ΅ΡΠ΅ΡΠ½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠ΅ Π‘Π½Π΅ΠΆΠ½Π°Ρ-ΠΠ΅ΠΆΠ΅Π½Π½ΠΎΠ³ΠΎ-ΠΠ»Π»ΡΠ·ΠΈΡ. Π ΡΠΎΡΡΠ°Π² Π²ΠΎΠ΄Π½ΡΡ
Ρ
Π΅ΠΌΠΎΠ³Π΅Π½Π½ΡΡ
ΠΎΡΠ»ΠΎΠΆΠ΅Π½ΠΈΠΉ Π²Ρ
ΠΎΠ΄ΡΡ Mg- ΠΈ Sr-ΡΠΎΠ΄Π΅ΡΠΆΠ°ΡΠΈΠΉ ΠΊΠ°Π»ΡΡΠΈΡ, Π°ΡΠ°Π³ΠΎΠ½ΠΈΡ, Π³ΠΈΠΏΡ, Π³ΠΈΠ΄ΡΠΎΠΌΠ°Π³Π½Π΅Π·ΠΈΡ, ΡΠ΅Π»Π΅ΡΡΠΈΠ½, ΡΡΡΠΎΠ½ΡΠΈΠ°Π½ΠΈΡ, Π΄ΠΎΠ»ΠΎΠΌΠΈΡ, Π³Π΅ΡΠΈΡ, ΡΡΡΠΈΠ» ΠΈ ΡΠΈΡΠΊΠΎΠ½. ΠΠΎΠ΄Π½ΡΠ΅ ΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΎΡΠ»ΠΎΠΆΠ΅Π½ΠΈΡ ΡΠ»ΠΎΠΆΠ΅Π½Ρ ΠΏΡΠ΅ΠΈΠΌΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎ Π΄ΠΎΠ»ΠΎΠΌΠΈΡΠΎΠΌ, ΠΊΠ²Π°ΡΡΠ΅ΠΌ ΠΈ ΠΊΠ°Π»ΡΡΠΈΡΠΎΠΌ. Π ΡΡ
ΠΎΠΆΠΈΡ
ΠΏΠΎ ΠΌΠΎΡΡΠΎΠ»ΠΎΠ³ΠΈΠΈ ΠΈ ΠΌΠΈΠΊΡΠΎΠΊΠ»ΠΈΠΌΠ°ΡΡ ΡΠ°ΡΡΡΡ
ΠΏΠ΅ΡΠ΅ΡΠ½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ Π½Π°Π±Π»ΡΠ΄Π°ΡΡΡΡ ΠΎΠ΄ΠΈΠ½Π°ΠΊΠΎΠ²ΡΠ΅ Π²ΡΠΎΡΠΈΡΠ½ΡΠ΅ ΠΌΠΈΠ½Π΅ΡΠ°Π»Ρ.Π£ ΡΡΠ°ΡΡΡ Π½Π°Π²ΠΎΠ΄ΡΡΡΡΡ Π²ΡΠ΄ΠΎΠΌΠΎΡΡΡ ΠΏΡΠΎ ΠΌΡΠ½Π΅ΡΠ°Π»ΡΠ½ΠΈΠΉ ΡΠΊΠ»Π°Π΄ Π²ΠΎΠ΄Π½ΠΈΡ
Ρ
Π΅ΠΌΠΎΠ³Π΅Π½Π½ΠΈΡ
Ρ Π²ΠΎΠ΄Π½ΠΈΡ
ΠΌΠ΅Ρ
Π°Π½ΡΡΠ½ΠΈΡ
Π²ΡΠ΄ΠΊΠ»Π°Π΄Π΅Π½Ρ Π² ΠΏΠ΅ΡΠ΅ΡΠ½ΡΠΉ ΡΠΈΡΡΠ΅ΠΌΡ Π‘Π½ΡΠΆΠ½Π°-ΠΠ΅ΠΆΠ΅Π½ΠΎΠ³ΠΎ-ΠΠ»ΡΠ·ΡΡ. ΠΠΎ ΡΠΊΠ»Π°Π΄Ρ Π²ΠΎΠ΄Π½ΠΈΡ
Ρ
Π΅ΠΌΠΎΠ³Π΅Π½Π½ΠΈΡ
Π²ΡΠ΄ΠΊΠ»Π°Π΄Π΅Π½Ρ Π²Ρ
ΠΎΠ΄ΡΡΡ ΠΊΠ°Π»ΡΡΠΈΡ, ΡΠΊΠΈΠΉ ΠΌΡΡΡΠΈΡΡ Mg Ρ Sr, Π°ΡΠ°Π³ΠΎΠ½ΡΡ, Π³ΡΠΏΡ, Π³ΡΠ΄ΡΠΎΠΌΠ°Π³Π½Π΅Π·ΡΡ, ΡΠ΅Π»Π΅ΡΡΠΈΠ½, ΡΡΡΠΎΠ½ΡΡΠ°Π½ΡΡ, Π΄ΠΎΠ»ΠΎΠΌΡΡ, Π³Π΅ΡΠΈΡ, ΡΡΡΠΈΠ» Ρ ΡΠΈΡΠΊΠΎΠ½. ΠΠΎΠ΄Π½Ρ ΠΌΠ΅Ρ
Π°Π½ΡΡΠ½Ρ Π²ΡΠ΄ΠΊΠ»Π°Π΄Π΅Π½Π½Ρ ΡΠΊΠ»Π°Π΄Π΅Π½Ρ ΠΏΠ΅ΡΠ΅Π²Π°ΠΆΠ½ΠΎ Π΄ΠΎΠ»ΠΎΠΌΡΡΠΎΠΌ, ΠΊΠ²Π°ΡΡΠΎΠΌ Ρ ΠΊΠ°Π»ΡΡΠΈΡΠΎΠΌ. Π£ ΡΡ
ΠΎΠΆΠΈΡ
Π·Π° ΠΌΠΎΡΡΠΎΠ»ΠΎΠ³ΡΡ ΡΠ° ΠΌΡΠΊΡΠΎΠΊΠ»ΡΠΌΠ°ΡΠΎΠΌ ΡΠ°ΡΡΠΈΠ½Π°Ρ
ΠΏΠ΅ΡΠ΅ΡΠ½ΠΎΡ ΡΠΈΡΡΠ΅ΠΌΠΈ ΡΠΏΠΎΡΡΠ΅ΡΡΠ³Π°ΡΡΡΡΡ ΠΎΠ΄Π½Π°ΠΊΠΎΠ²Ρ Π²ΡΠΎΡΠΈΠ½Π½Ρ ΠΌΡΠ½Π΅ΡΠ°Π»ΠΈ.The article presents the preliminary characteristic of the mineral composition of chemogenic formations and clastic deposits of Snezhnaya-Mezhennogo-Illusia cave system. Chemogenic formations are composed by Mg- and Sr-calcite, aragonite, gypsum and hydromagnesite, celestite, strontianite, dolomite, goethite, rutile and zircon. Clastic sediments are composed mainly by dolomite, quartz and calcite. Same secondary minerals are observed in those parts of the cave system that have similar morphology and microclimate
Resonant excitations of single and two-qubit systems coupled to a tank circuit
The interaction of flux qubits with a low frequency tank circuit is studied.
It is shown that changes in the state of the interacting qubits influence the
effective impedance of the circuit, which is the essence of the so-called
impedance measurement technique. The multiphoton resonant excitations in both
single flux qubits and pairs of coupled flux qubits are investigated. In
particular, we compare our theoretical results with recent spectroscopy
measurements, Landau-Zener interferometry, and multiphoton fringes.Comment: 11 pages, 11 figures; v.2: minor change
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