Topological rf SQUID with a frustrating<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>π</mml:mi></mml:math>junction for probing the Majorana bound state

Lucignano, P.; Tafuri, F.; Tagliacozzo, A.

doi:10.1103/physrevb.88.184512

Cited by 25 publications

(16 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Everything has to be finely tuned and the temperature has to be quite low, usually below 100mK. That is why many other proposals involving high critical temperature superconductors (Lucignano et al, 2012(Lucignano et al, , 2013 or completely different platforms (Nadj-Perge et al, 2014;Hart et al, 2014) have been investigated, too.…”

Section: B Diffusive Limit: Weak Anti-localizationmentioning

confidence: 99%

Quantum transport in Rashba spin–orbit materials: a review

2015

View full text Add to dashboard Cite

In this review article we describe spin-dependent transport in materials with spin-orbit interaction of Rashba type. We mainly focus on semiconductor heterostructures, however we consider topological insulators, graphene and hybrid structures involving superconductors as well. We start from the Rashba Hamiltonian in a two dimensional electron gas and then describe transport properties of two- and quasi-one-dimensional systems. The problem of spin current generation and interference effects in mesoscopic devices is described in detail. We address also the role of Rashba interaction on localisation effects in lattices with nontrivial topology, as well as on the Ahronov-Casher effect in ring structures. A brief section, in the end, describes also some related topics including the spin-Hall effect, the transition from weak localisation to weak anti localisation and the physics of Majorana fermions in hybrid heterostructures involving Rashba materials in the presence of superconductivity.

show abstract

Section: B Diffusive Limit: Weak Anti-localizationmentioning

confidence: 99%

Quantum transport in Rashba spin–orbit materials: a review

2015

View full text Add to dashboard Cite

show abstract

“…Hybrid devices involving interfaces between HTSs and, for example, topological insulators (TIs) or graphene are extremely promising to reveal the new physics due to the proximity of a superconductor and a two-dimensional material with a Dirac cone [1][2][3]. There are several theoretical reports, which refer to the d-wave symmetry of the order parameter in HTSs and to the large value of the superconducting gap, to design experiments to stabilize and reveal the existence of Majorana fermions, still elusive particles in solid-state systems, that are supposed to nucleate at the interface between a superconductor and a TI [4][5][6][7][8]. Superconducting hybrid structures are also considered a crucial step towards a topological quantum computer, which would be exceptionally well protected from errors, thanks to the non-Abelian statistics of Majorana fermions [9,10].…”

Section: Introductionmentioning

confidence: 99%

Fabricating Nanogaps inYBa2Cu3O7−δ
Baghdadi
¹
,
Arpaia
²
,
Charpentier
³

et al. 2015
Phys. Rev. Applied
21
1
25
0
View full text Add to dashboard Cite

The advances of nanotechnologies applied to high-critical-temperature superconductors (HTSs) have recently given a huge boost to the field, opening new prospectives for their integration in hybrid devices. The feasibility of this research goes through the realization of HTS nanogaps with superconductive properties close to the as-grown bulk material at the nanoscale. Here we present a fabrication approach allowing the realization of YBa 2 Cu 3 O 7−δ (YBCO) nanogaps with dimensions as small as 35 nm. To assess the quality of the nanogaps, we measure, before and after an ozone treatment, the current-voltage characteristics and the resistance versus temperature of YBCO nanowires with various widths and lengths, fabricated by using different lithographic processes. The analysis of the superconducting transition with a thermally activated vortex-entry model allows us to determine the maximum damage the nanowires undergo during the patterning which relates to the upper bound for the dimension of the nanogap. We find that the effective width of the nanogap is of the order of 100 nm at the superconducting transition temperature while retaining the geometrical value of about 35 nm at lower temperatures. The feasibility of the nanogaps for hybrid Josephson devices is demonstrated by bridging them with thin Au films. We detect a Josephson coupling up to 85 K with an almost ideal magnetic-field response of the Josephson current. These results pave the way for the realization of complex hybrid devices, where tiny HTS nanogaps can be instrumental to study the Josephson effect through barriers such as topological insulators or graphene.

show abstract

“…89 In contrast to these wire structures, we investigate the quasiparticle excitations, including possible Majorana modes, in quantum dots (QDs) and quantum rings (QRs) with (possibly induced) p-wave pairing. While there are several works on the ring geometry for the chiral p-wave superconductor and related models, 17,62,63,[90][91][92][93] our focus is on providing an in-depth analysis of the system and of the effects of finite size or magnetic fields penetrating into the superconducting region.…”

Section: Introductionmentioning

confidence: 99%

Probing Majorana-like states in quantum dots and quantum rings

Scharf

Žutić

2015

Phys. Rev. B

View full text Add to dashboard Cite

Engineering chiral p-wave superconductivity in semiconductor structures offers fascinating ways to obtain and study Majorana modes in a condensed matter context. Here, we theoretically investigate chiral p-wave superconductivity in quantum dots and quantum rings. Using both analytical as well as numerical methods, we calculate the quasiparticle excitation spectra in these structures and the corresponding excitation amplitudes and charge densities. In the topological regime, we can observe the chiral edge modes localized at the boundaries and possessing finite energy in quantum dots and quantum rings. By applying a magnetic field which is expelled from the quantum ring, but which creates a flux that is an odd integer multiple of Φ0/2 = π /e, Majorana modes, that is, (approximately) degenerate edge modes with zero energy and zero charge density, become possible in the topological regime. Furthermore, we investigate finite-size effects that split these degenerate edge modes as well as the effect of a magnetic field penetrating into the superconducting region that can under certain circumstances still support edge modes with approximately zero energy and charge.

show abstract

Topological rf SQUID with a frustratingπjunction for probing the Majorana bound state

Cited by 25 publications

References 33 publications

Quantum transport in Rashba spin–orbit materials: a review

Quantum transport in Rashba spin–orbit materials: a review

Fabricating Nanogaps inYBa2Cu3O7−δ
Baghdadi
¹
,
Arpaia
²
,
Charpentier
³

et al. 2015
Phys. Rev. Applied
21
1
25
0
View full text Add to dashboard Cite

Probing Majorana-like states in quantum dots and quantum rings

Contact Info

Product

Resources

About

Topological rf SQUID with a frustratingπjunction for probing the Majorana bound state

Cited by 25 publications

References 33 publications

Quantum transport in Rashba spin–orbit materials: a review

Quantum transport in Rashba spin–orbit materials: a review

Fabricating Nanogaps inYBa2Cu3O7−δBaghdadi1, Arpaia2, Charpentier3 et al. 2015Phys. Rev. Applied211250View full textAdd to dashboardCite

Probing Majorana-like states in quantum dots and quantum rings

Contact Info

Product

Resources

About

Fabricating Nanogaps inYBa2Cu3O7−δ
Baghdadi
¹
,
Arpaia
²
,
Charpentier
³

et al. 2015
Phys. Rev. Applied
21
1
25
0
View full text Add to dashboard Cite