[Une chaîne supraconductrice comme simulateur de transitions de phases quantiques en une dimension]
Nous proposons une nouvelle plateforme pour l'étude des transitions de phase quantiques en une dimension. Le système consiste en une chaîne de boucles de SQUID asymétriques spécialement configurées : chaque SQUID contient plusieurs jonctions Josephson, dont une partagée avec le SQUID voisin. Des expériences sous micro-ondes électromagnétiques nous ont permis d'explorer les lignes de transition entre phase ordonnée et phase désordonnée, ainsi que le comportement critique des états excités de plus basse énergie au voisinage de cette transition. Grâce à la flexibilité de la configuration des SQUIDS et à la possibilité de contrôler individuellement les paramètres de chaque jonction Josephson, ce système permettra d'explorer, lors de prochaines expériences, les effets de la non-intégrabilité ou du désordre sur cette transition de phase quantique en une dimension.
We propose a novel platform for the study of quantum phase transitions in one dimension (1D QPT). The system consists of a specially designed chain of asymmetric SQUIDs; each SQUID contains several Josephson junctions with one junction shared between the nearest-neighbor SQUIDs. We develop the theoretical description of the low-energy part of the spectrum. In particular, we show that the system exhibits a quantum phase transition of Ising type. In the vicinity of the transition, the low-energy excitations of the system can be described by Majorana fermions. This allows us to compute the matrix elements of the physical perturbations in the low-energy sector. In the microwave experiments with this system, we explored the phase boundaries between the ordered and disordered phases and the critical behavior of the system's low-energy modes close to the transition. Due to the flexible chain design and control of the parameters of individual Josephson junctions, future experiments will be able to address the effects of non-integrability and disorder on the 1D QPT.
Mots-clés : Simulations quantiques, Transitions de phase quantiques, Chaînes des jonctions Josephson, Chaîne d'Ising quantique en champ transverse
Matthew T. Bell 1 ; Benoît Douçot 2 ; Michael E. Gershenson 3 ; Lev B. Ioffe 2 ; Aleksandra Petković 4
@article{CRPHYS_2018__19_6_484_0,
author = {Matthew T. Bell and Beno{\^\i}t Dou\c{c}ot and Michael E. Gershenson and Lev B. Ioffe and Aleksandra Petkovi\'c},
title = {Josephson ladders as a model system for {1D} quantum phase transitions},
journal = {Comptes Rendus. Physique},
pages = {484--497},
publisher = {Elsevier},
volume = {19},
number = {6},
year = {2018},
doi = {10.1016/j.crhy.2018.09.002},
language = {en},
}
TY - JOUR AU - Matthew T. Bell AU - Benoît Douçot AU - Michael E. Gershenson AU - Lev B. Ioffe AU - Aleksandra Petković TI - Josephson ladders as a model system for 1D quantum phase transitions JO - Comptes Rendus. Physique PY - 2018 SP - 484 EP - 497 VL - 19 IS - 6 PB - Elsevier DO - 10.1016/j.crhy.2018.09.002 LA - en ID - CRPHYS_2018__19_6_484_0 ER -
%0 Journal Article %A Matthew T. Bell %A Benoît Douçot %A Michael E. Gershenson %A Lev B. Ioffe %A Aleksandra Petković %T Josephson ladders as a model system for 1D quantum phase transitions %J Comptes Rendus. Physique %D 2018 %P 484-497 %V 19 %N 6 %I Elsevier %R 10.1016/j.crhy.2018.09.002 %G en %F CRPHYS_2018__19_6_484_0
Matthew T. Bell; Benoît Douçot; Michael E. Gershenson; Lev B. Ioffe; Aleksandra Petković. Josephson ladders as a model system for 1D quantum phase transitions. Comptes Rendus. Physique, Quantum simulation / Simulation quantique, Volume 19 (2018) no. 6, pp. 484-497. doi : 10.1016/j.crhy.2018.09.002. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2018.09.002/
[1] Nature physics, Nature physics insight – quantum simulation, 2012.
[2] Simple universal models capture all classical spin physics, Science, Volume 351 (2016) no. 6278, pp. 1180-1183
[3] Universal quantum Hamiltonians, 2017 | arXiv
[4] Quantum simulations with ultracold quantum gases, Nat. Phys., Volume 8 (2012), pp. 267-276
[5] et al. A cold-atom Fermi–Hubard antiferromagnet, Nature, Volume 545 (2017), p. 462
[6] Quantum simulations with trapped ions, Nat. Phys., Volume 8 (2012), p. 277
[7] On-chip quantum simulations with superconducting circuits, Nat. Phys., Volume 8 (2012), p. 292
[8] Quantum Phase Transitions in Transverse Field Spin Models: From Statistical Physics to Quantum Information, Cambridge University Press, Cambridge, UK, 2015
[9] Quantum Phase Transitions, Cambridge University Press, Cambridge, 1999
[10] Quantum annealing with manufactured spins, Nature, Volume 473 (2011), pp. 195-198
[11] Quantum critical behavior for a model magnet, Phys. Rev. Lett., Volume 77 (1996), pp. 940-943
[12] Magnetic excitations near the quantum phase transition in the Ising ferromagnet, Phys. Rev. B, Volume 75 (2007)
[13] Quantum criticality in an Ising chain: experimental evidence for emergent E8 symmetry, Science, Volume 327 (2010), pp. 177-180
[14] Quantum superinductor with tunable non-linearity, Phys. Rev. Lett., Volume 109 (2012), pp. 1-5 (137003)
[15] Introduction to Superconductivity, Dover Books, 2004
[16] Int. J. Mod. Phys. A, 11 (1996), p. 2765
[17] Protected Josephson rhombus chains, Phys. Rev. Lett., Volume 112 (2014)
[18] Spectroscopic evidence of the Aharonov–Casher effect in a cooper pair box, Phys. Rev. Lett., Volume 116 (2016)
[19] Approaching unit visibility for control of a superconducting qubit with dispersive readout, Phys. Rev. Lett., Volume 95 ( 5 August 2005 ) no. 6
[20] Unpaired Majorana modes in Josephson-junction arrays with gapless bulk excitations, Phys. Rev. Lett., Volume 115 (2015)
Cité par Sources :
Commentaires - Politique