Signatures of Majorana Fermions in Hybrid Superconductor-Semiconductor Nanowire Devices

Mourik, Vincent; Zuo, Kun; Frolov, Sergey; Plissard, Sébastien; Bakkers, Epam Erik; Kouwenhoven, Leo P.

doi:10.1126/science.1222360

Cited by 4,073 publications

(4,813 citation statements)

References 119 publications

Supporting

119

Mentioning

4,675

Contrasting

Unclassified

Order By: Relevance

“…InAs and InSb nanowires offer an interesting platform for fundamental studies and electronic applications [1][2][3][4][5][6][7][8]. For high performance devices it is important to achieve high material purity, a defect-free crystal structure [9], and flexibility in terms of dimensions, morphology and growth direction [10,11].…”

Section: Introductionmentioning

confidence: 99%

Tuning growth direction of catalyst-free InAs(Sb) nanowires with indium droplets

et al. 2016

View full text Add to dashboard Cite

The need for indium droplets to initiate self-catalyzed growth of InAs nanowires has been highly debated in the last few years. Here, we report on the use of indium droplets to tune the growth direction of self-catalyzed InAs nanowires. The indium droplets are formed in situ on InAs(Sb) stems. Their position is modified to promote growth in the 〈11-2〉 or equivalent directions. We also show that indium droplets can be used for the fabrication of InSb insertions in InAsSb nanowires. Our results demonstrate that indium droplets can initiate growth of InAs nanostructures as well as provide added flexibility to nanowire growth, enabling the formation of kinks and heterostructures, and offer a new approach in the growth of defect-free crystals.S Online supplementary data available from stacks.iop.org/NANO/28/054001/mmedia

show abstract

Section: Introductionmentioning

confidence: 99%

Tuning growth direction of catalyst-free InAs(Sb) nanowires with indium droplets

et al. 2016

View full text Add to dashboard Cite

show abstract

“…This non-local nature of Majorana fermions gives stability to the qubit, which makes Majorana fermions a promising candidate for a quantum information carrier. Physical realizations of the Kitaev model, and also of Majorana zero-energy bound states, have been pursued experimentally using quantum wires with spin-orbit interactions under magnetic fields, attached to the s-wave superconductor 125 , and also with one-dimensional arrays of magnetic impurities on s-wave superconductors 126 . To truly establish a Majorana bound state, a smoking gun experiment, using a phase-sensitive probe, is still highly desirable 127,128 .…”

Section: Quantum Computingmentioning

confidence: 99%

Emergent functions of quantum materials

2017

View full text Add to dashboard Cite

Materials can harbour quantum many-body systems, most typically in the form of strongly correlated electrons in solids, that lead to novel and remarkable functions thanks to emergence-collective behaviours that arise from strong interactions among the elements. These include the Mott transition, high-temperature superconductivity, topological superconductivity, colossal magnetoresistance, giant magnetoelectric e ect, and topological insulators. These phenomena will probably be crucial for developing the next-generation quantum technologies that will meet the urgent technological demands for achieving a sustainable and safe society. Dissipationless electronics using topological currents and quantum spins, energy harvesting such as photovoltaics and thermoelectrics, and secure quantum computing and communication are the three major fields of applications working towards this goal. Here, we review the basic principles and the current status of the emergent phenomena and functions in materials from the viewpoint of strong correlation and topology.E mergence is a concept developed for many-body systems, indicating the properties, phenomena, and functions that never appear in the individual elements but are realized only when a huge number of elements get together 1 . Inside materials, emergent phenomena are often seen due to the interaction of electronic states; with recent developments on electronic states in solids schematically summarized in Fig. 1a. Electrons in solids have several degrees of freedom: charge, spin and orbital, and are characterized by the topological nature determined by the atomic potential on the crystal lattice structure, as schematically shown in Fig. 1b. These five attributes are coupled together and determine the overall responses to stimuli, which appear as materials' electrical, magnetic, optical, thermal, and mechanical properties.These collective electrons demonstrate various macroscopic quantum phenomena, the representative example of which is superconductivity. One of the big challenges in condensed matter physics is to increase the temperature (T c ) at which superconductivity can be observed to above room temperature. However, there are many other macroscopic quantum phenomena that are already observable above room temperature. One is magnetism (by the Bohr-van Leeuwen theorem), and the other is ferroelectricity 2,3 . Remarkably, there are common features of these three macroscopic quantum phenomena: the order parameter, which is of quantum origin, behaves as a classical quantity, and the quantum topology plays a crucial role.The topological nature of the electronic states is the key concept in the most recent developments in understanding quantum materials. The quantum Hall effect, topological insulators, and topological superconductors are all characterized by nontrivial topologies in Hilbert space. The Berry phase, which describes the connection and curvature of the subspace of Hilbert space, plays the central role in the unified principle to describe this topological nature 4 . ...

show abstract

“…13 Indeed signatures of MFs have been reported in hybrid semiconductor−superconductor InSb nanowire devices. 14 While in InSb nanowires the basic properties of spin−orbit interaction and induced superconductivity have each been separately investigated, the degree of fulfillment of the third requirement for creation of MFs, the 1D semiconductor wire, is not as well understood. In a 1D wire transport takes place in subbands, of which the occupation is controlled by an external gate voltage.…”

mentioning

confidence: 99%

Quantized Conductance in an InSb Nanowire

et al. 2012

View full text Add to dashboard Cite

Ballistic one-dimensional transport in semiconductor nanowires plays a central role in creating topological and helical states. The hallmark of such one-dimensional transport is conductance quantization. Here we show conductance quantization in InSb nanowires at nonzero magnetic fields. Conductance plateaus are studied as a function of source-drain bias and magnetic field, enabling extraction of the Landég factor and the subband spacing. KEYWORDS:Conductance quantization, ballistic transport, quantum point contact, subband, nanowire, InSb S emiconductor nanowires are the starting point of recently proposed topological systems. 1−3 A topological superconducting region arises in a one-dimensional (1D) semiconductor wire in the presence of a strong spin−orbit coupling when it is brought in contact with a superconducting material. On the boundary of the topological and nontopological wire regions Majorana fermions (MFs) are expected. 4 The MFs in a nanowire, quasi-particles that are an equal superposition of an electron and a hole, are candidate building blocks for faulttolerant quantum computation. 4,5 Moreover, 1D semiconductor wires with strong spin−orbit coupling have also been identified as a suitable platform for creation of a helical state. 6−8 In such a state spin and momentum of an electron are perfectly correlated, thereby creating spin polarization and allowing spin filtering, key themes in the field of spintronics. 9−11 InSb nanowires, alongside InAs and Si/Ge core−shell nanowires, are promising for study of topological and helical states, as they have a strong spin−orbit interaction, 12 and superconductivity can be induced in the nanowires. 13 Indeed signatures of MFs have been reported in hybrid semiconductor−superconductor InSb nanowire devices. 14 While in InSb nanowires the basic properties of spin−orbit interaction and induced superconductivity have each been separately investigated, the degree of fulfillment of the third requirement for creation of MFs, the 1D semiconductor wire, is not as well understood. In a 1D wire transport takes place in subbands, of which the occupation is controlled by an external gate voltage. While first schemes for detection of MFs required occupation of only a single subband near the superconducting contacts where the MFs form, 1,2 later proposals extended this condition to the multisubband regime. 15−17 Information about the energy spectrum of InSb nanowires needed to answer questions of subband occupation is however lacking. Moreover, MFs are affected by disorder in the wire, 17−19 of which the extent is unknown. Such disorder creates diffusive transport, instead of the ballistic transport implied in the 1D requirement. Subband occupation and disorder are also key issues in creation of helical states in InSb nanowires.The formation of subbands in (ballistic) 1D wires is shown in transport measurements by quantization of conductance, where each spin-degenerate subband contributes a conductance of g Q = 2e 2 /h. 20,21 In semiconductor nanowires conductan...

show abstract

Signatures of Majorana Fermions in Hybrid Superconductor-Semiconductor Nanowire Devices

Cited by 4,073 publications

References 119 publications

Tuning growth direction of catalyst-free InAs(Sb) nanowires with indium droplets

Tuning growth direction of catalyst-free InAs(Sb) nanowires with indium droplets

Emergent functions of quantum materials

Quantized Conductance in an InSb Nanowire

Contact Info

Product

Resources

About