Phase transition in a chain of quantum vortices

Bruder, Christoph; Glazman, L. I.; Larkin, A. I.; Mooij, J. E.; Oudenaarden, Alexander van

doi:10.1103/physrevb.59.1383

Cited by 16 publications

(26 citation statements)

References 19 publications

(43 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As a result, the effective potential acquires the form of a periodic 1D lattice of pinning sites separated by a uniform spacing a = L/N, where N = I[BwL/ 0 ] (with 0 = hc/2e the flux quantum, and I[z] the integer value of z) denotes the total number of vortices. 10 Assuming further that the high vortex density in this case leads to near merging of their cores along the central axis of the strip, the system becomes essentially equivalent to a line-junction formed by a pair of parallel SC wires separated by a normal barrier [ Fig. 1(b)], subject to a magnetic field B perpendicular to the junction plane.…”

Section: Modelmentioning

confidence: 99%

See 1 more Smart Citation

Alternating superconductor-insulator transport characteristics in a quantum vortex chain

Atzmon

Shimshoni

2012

Phys. Rev. B

View full text Add to dashboard Cite

Experimental studies of magnetoresistance in thin superconducting strips subject to a perpendicular magnetic field B exhibit a multitude of transitions, from superconductor to insulator and vice versa. Motivated by this observation, we study a theoretical model for the transport properties of a ladderlike superconducting device close to a superconductor-insulator transition. In this regime, strong quantum fluctuations dominate the dynamics of the vortex chain forming along the device. Utilizing a mapping of the vortex system at low energies to one-dimensional fermions at a chemical potential dictated by B, we find that a quantum phase transition of the Ising type occurs at critical values of the vortex filling, from a superconducting phase near integer filling to an insulator near half filling. The current-voltage (I-V) characteristics of the weakly disordered device in the presence of a d.c. current bias I is evaluated, and investigated as a function of B, I , the temperature T , and the disorder strength. In the Ohmic regime (I/e T ), the resulting magnetoresistance R(B) exhibits oscillations similar to the experimental observation. More generally, we find that the I-V characteristics of the system manifests a dramatically distinct behavior in the superconducting and insulating regimes.

show abstract

Section: Modelmentioning

confidence: 99%

“…It is therefore possible to model it as a two-leg bosonic ladder 13 (or, equivalently, a ladderlike Josephson array), 10 where a coordinate x = ja (j integer) denotes the locations of vortex cores in the continuum limit. The dynamics of the phase field in the wires [φ n (x,t) with n = 1,2] is governed by the effective 1D Hamiltonian…”

Section: Modelmentioning

confidence: 99%

Alternating superconductor-insulator transport characteristics in a quantum vortex chain

Atzmon

Shimshoni

2012

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…Inset: R vs. the gap ∆ d [see Eq. (15) and text therafter] near a single critical point, for T = 0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5K.R(B) exhibits oscillations which amplitude is sharply increasing at low T , in striking resemblance to the behavior of Josephson arrays [10] and SC network systems [11]. Moreover, the SIT at B c appears to be preempted by several consecutive transitions at lower fields, from a SC to an insulator or vice versa alternately.The periodicity of the above mentioned oscillations is consistent with a single flux penetration to the sample, suggesting that the observed SC or insulating behavior of the system is determined by commensuration of vortices within the strip area.…”

mentioning

confidence: 93%

“…When an integer number of vortices can be fitted along the strip length, superconductivity may be supported even at sufficiently high B such that a large fraction of the sample area turns normal. Deviation from commensurability of the vortex filling weakens superconductivity, possibly inducing a transition to a metallic [10] or insulating state.In this paper we focus on the strongly quantum fluctu-…”

mentioning

confidence: 99%

Superconductor-insulator transitions and magnetoresistance oscillations in superconducting strips

Atzmon

Shimshoni

2011

Phys. Rev. B

View full text Add to dashboard Cite

The magnetoresistance of thin superconducting (SC) strips subject to a perpendicular magnetic field B and low temperatures T manifests a sequence of alternating SC-insulator transitions (SIT). We study this phenomenon within a quasi one-dimensional (1D) model for the quantum dynamics of vortices in a line-junction between coupled parallel SC wires, at parameters close to their SIT. Mapping the vortex system to 1D Fermions at a chemical potential dictated by B, we find that a quantum phase transition of the Ising type occurs at critical values of the vortex filling, from a SC phase near integer filling to an insulator near 1/2-filling. For T → 0, the resulting magnetoresistance R(B) exhibits oscillations similar to the experimental observation.PACS numbers: 05.30.Rt, 75.10.Jm, 71.10.Pm, 74.25.Uv, 74.81.Fa The conduction properties of low-dimensional superconducting (SC) systems (thin films and wires) are strongly dominated by fluctuations in the SC order parameter. A particularly prominent manifestation of the role of fluctuations is the appearance of a finite dissipative resistance below the mean-field critical temperature T c of the bulk superconductor. At low temperatures T ≪ T c , the dominant fluctuations are in the phase of the complex order parameter. Most notably, topological excitations (vortices and phase-slips) can generate dissipation in their liquid state. In the T → 0 limit, their quantum dynamics becomes significant and may drive a transition to a metallic or insulating state [1,2].In the one-dimensional (1D) case, i.e. SC wires of width and thickness smaller than the coherence length ξ, the resistance essentially never vanishes at finite T due to thermal activation of phase-slips [3, 4] (for T T c ) or their quantum tunneling at lower T [2, 5, 6]. In contrast, in the 2D case (SC films) superconductivity is wellestablished at sufficiently low T . However, a quantum (T → 0) superconductor-insulator transition (SIT) [1,7] can be tuned by an external parameter which leads to proliferation of free vortices. Employing charge-flux duality [8] it is possible to view the SC phase as a vortex solid, and the insulator as a vortex superfluid.A convenient means of inducing a SIT in SC films is by application of a perpendicular magnetic field B. At fixed T , a positive magnetoresistance R(B) is typically observed in a wide range of B. The SIT is then clearly indicated in the data as a crossing point of these isotherms at a critical field B c , separating a SC phase (where dR/dT > 0) for B < B c from the insulating phase (dR/dT < 0) for B > B c .A recent experimental study of a strip geometry [9] -namely, a SC wire of width comparable to ξ -offers an opportunity to probe the crossover from a 1D to 2D quantum dynamics of the topological phase-defects in SC devices. The prominent observation is that in the presence of a perpendicular field B, the magnetoresistance R(B) exhibits oscillations which amplitude is sharply increasing at low T , in striking resemblance to the behavior of Josephson arrays [10] and SC ...

show abstract

“…15 were later interpreted to be consistent with a purely classical commensurability transition rather than the quantum Mott transition. 18 The suppression of quantum effects in these experiments stemmed from the low inductance of the continuous superconducting wires, which were necessary to make the Josephson junction arrays.…”

Section: Introductionmentioning

confidence: 99%

Signatures of quantum phase transitions in the dynamic response of fluxonium qubit chains

et al. 2015

View full text Add to dashboard Cite

We evaluate the microwave admittance of a one-dimensional chain of fluxonium qubits coupled by shared inductors. Despite its simplicity, this system exhibits a rich phase diagram. A critical applied magnetic flux separates a homogeneous ground state from a phase with a ground state exhibiting inhomogeneous persistent currents. Depending on the parameters of the array, the phase transition may be a conventional continuous one, or of a commensurate-incommensurate nature. Furthermore, quantum fluctuations affect the transition and possibly lead to the presence of gapless "floating phases". The signatures of the soft modes accompanying the transitions appear as a characteristic frequency dependence of the dissipative part of admittance.

show abstract

Phase transition in a chain of quantum vortices

Cited by 16 publications

References 19 publications

Alternating superconductor-insulator transport characteristics in a quantum vortex chain

Alternating superconductor-insulator transport characteristics in a quantum vortex chain

Superconductor-insulator transitions and magnetoresistance oscillations in superconducting strips

Signatures of quantum phase transitions in the dynamic response of fluxonium qubit chains

Contact Info

Product

Resources

About