The fractional a.c. Josephson effect in a semiconductor–superconductor nanowire as a signature of Majorana particles

Nature Physics - Tập 8 Số 11 - Trang 795-799 - 2012
Rokhinson, Leonid P.1, Liu, Xinyu2, Furdyna, Jacek K.2
1Department of Physics, Birck Nanotechnology Center and School of Electrical and Computer Engineering, Purdue University, USA
2Department of Physics, University of Notre Dame, USA

Tóm tắt

The fractional alternating-current Josephson effect produces a series of steps in the current–voltage characteristics of a superconducting junction driven at radiofrequencies. This unusual phenomenon is now observed in a semiconductor–superconductor nanowire. What is more, a doubling in step size when a strong magnetic field is applied could be a possible signature of Majorana fermions, particles that are their own antiparticle. Topological superconductors that support Majorana fermions have been predicted when one-dimensional semiconducting wires are coupled to a superconductor1,2,3. Such excitations are expected to exhibit non-Abelian statistics and can be used to realize quantum gates that are topologically protected from local sources of decoherence4,5. Here we report the observation of the fractional a.c. Josephson effect in a hybrid semiconductor–superconductor InSb/Nb nanowire junction, a hallmark of topological matter. When the junction is irradiated with a radiofrequency f0 in the absence of an external magnetic field, quantized voltage steps (Shapiro steps) with a height Δ V = h f0/2e are observed, as is expected for conventional superconductor junctions, where the supercurrent is carried by charge- 2e Cooper pairs. At high magnetic fields the height of the first Shapiro step is doubled to h f0/e, suggesting that the supercurrent is carried by charge- e quasiparticles. This is a unique signature of the Majorana fermions, predicted almost 80 years ago6.

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citation_journal_title=Phys. Rev. Lett.; citation_title=Majorana fermions and a topological phase transition in semiconductor–superconductor heterostructures; citation_author=RM Lutchyn, JD Sau, SD Sarma; citation_volume=105; citation_publication_date=2010; citation_pages=077001; citation_doi=10.1103/PhysRevLett.105.077001; citation_id=CR1

citation_journal_title=Phys. Rev. Lett.; citation_title=Helical liquids and Majorana bound states in quantum wires; citation_author=Y Oreg, G Refael, F von Oppen; citation_volume=105; citation_publication_date=2010; citation_pages=177002; citation_doi=10.1103/PhysRevLett.105.177002; citation_id=CR2

citation_journal_title=Nature Phys.; citation_title=Non-Abelian statistics and topological quantum information processing in 1D wire networks; citation_author=J Alicea, Y Oreg, G Refael, F von Oppen, MPA Fisher; citation_volume=7; citation_publication_date=2011; citation_pages=412-417; citation_doi=10.1038/nphys1915; citation_id=CR3

citation_journal_title=Phys.-Usp.; citation_title=Unpaired Majorana fermions in quantum wires; citation_author=AY Kitaev; citation_volume=44; citation_publication_date=2001; citation_pages=131-136; citation_doi=10.1070/1063-7869/44/10S/S29; citation_id=CR4

citation_journal_title=Ann. Phys.; citation_title=Fault-tolerant quantum computation by anyons; citation_author=AY Kitaev; citation_volume=303; citation_publication_date=2003; citation_pages=2-30; citation_doi=10.1016/S0003-4916(02)00018-0; citation_id=CR5

citation_journal_title=Nuovo Cimento.; citation_title=Symmetrical theory of electrons and positrons; citation_author=E Majorana; citation_volume=14; citation_publication_date=1937; citation_pages=171-184; citation_doi=10.1007/BF02961314; citation_id=CR6

citation_journal_title=Proc. R. Soc. Lond. A; citation_title=The quantum theory of the electron; citation_author=PAM Dirac; citation_volume=117; citation_publication_date=1928; citation_pages=610-624; citation_doi=10.1098/rspa.1928.0023; citation_id=CR7

citation_journal_title=Nature Phys.; citation_title=Majorana returns; citation_author=F Wilczek; citation_volume=5; citation_publication_date=2009; citation_pages=614-618; citation_doi=10.1038/nphys1380; citation_id=CR8

citation_journal_title=Science; citation_title=The sterile neutrino: Fertile concept or dead end?; citation_author=A Cho; citation_volume=334; citation_publication_date=2011; citation_pages=304-306; citation_doi=10.1126/science.334.6054.304; citation_id=CR9

citation_journal_title=Nucl. Phys. B; citation_title=Nonabelions in the fractional quantum Hall effect; citation_author=G Moore, N Read; citation_volume=360; citation_publication_date=1991; citation_pages=362-396; citation_doi=10.1016/0550-3213(91)90407-O; citation_id=CR10

citation_journal_title=Phys. Rev. B; citation_title=Midgap edge states and pairing symmetry of quasi-one-dimensional organic superconductors; citation_author=K Sengupta, I Žutić, H-J Kwon, VM Yakovenko, S Das Sarma; citation_volume=63; citation_publication_date=2001; citation_pages=144531; citation_doi=10.1103/PhysRevB.63.144531; citation_id=CR11

citation_journal_title=Phys. Rev. B; citation_title=Proposal to stabilize and detect half-quantum vortices in strontium ruthenate thin films: Non-abelian braiding statistics of vortices in a p+i p superconductor; citation_author=S Das Sarma, C Nayak, S Tewari; citation_volume=73; citation_publication_date=2006; citation_pages=220502; citation_doi=10.1103/PhysRevB.73.220502; citation_id=CR12

citation_journal_title=Phys. Rev. B; citation_title=Paired states of fermions in two dimensions with breaking of parity and time-reversal symmetries and the fractional quantum Hall effect; citation_author=N Read, D Green; citation_volume=61; citation_publication_date=2000; citation_pages=10267-10297; citation_doi=10.1103/PhysRevB.61.10267; citation_id=CR13

citation_journal_title=Phys. Rev. Lett.; citation_title=Superconducting proximity effect and Majorana fermions at the surface of a topological insulator; citation_author=L Fu, C Kane; citation_volume=100; citation_publication_date=2008; citation_pages=096407; citation_doi=10.1103/PhysRevLett.100.096407; citation_id=CR14

citation_journal_title=Phys. Rev. Lett.; citation_title=Generic new platform for topological quantum computation using semiconductor heterostructures; citation_author=J Sau, R Lutchyn, S Tewari, S Das Sarma; citation_volume=104; citation_publication_date=2010; citation_pages=040502; citation_doi=10.1103/PhysRevLett.104.040502; citation_id=CR15

citation_journal_title=Nature Phys.; citation_title=Observation of a one-dimensional spin–orbit gap in a quantum wire; citation_author=C Quay; citation_volume=6; citation_publication_date=2010; citation_pages=336-339; citation_doi=10.1038/nphys1626; citation_id=CR16

citation_journal_title=Phys. Rev. B; citation_title=Majorana fermions in a tunable semiconductor device; citation_author=J Alicea; citation_volume=81; citation_publication_date=2010; citation_pages=125318; citation_doi=10.1103/PhysRevB.81.125318; citation_id=CR17

citation_journal_title=Phys. Rev. Lett.; citation_title=Search for Majorana fermions in multiband semiconducting nanowires; citation_author=RM Lutchyn, T Stanescu, SD Sarma; citation_volume=106; citation_publication_date=2011; citation_pages=127001; citation_doi=10.1103/PhysRevLett.106.127001; citation_id=CR18

citation_journal_title=Phys. Rev. Lett.; citation_title=Multichannel generalization of Kitaev’s Majorana end states and a practical route to realize them in thin films; citation_author=AC Potter, PA Lee; citation_volume=105; citation_publication_date=2010; citation_pages=227003; citation_doi=10.1103/PhysRevLett.105.227003; citation_id=CR19

citation_journal_title=Phys. Rev. B; citation_title=Majorana fermions in semiconductor nanowires; citation_author=T Stanescu, RM Lutchyn, SD Sarma; citation_volume=84; citation_publication_date=2011; citation_pages=144522; citation_doi=10.1103/PhysRevB.84.144522; citation_id=CR20

citation_journal_title=Phys. Rev. Lett.; citation_title=Majorana fermion induced resonant Andreev reflection; citation_author=KT Law, PA Lee, TK Ng; citation_volume=103; citation_publication_date=2009; citation_pages=237001; citation_doi=10.1103/PhysRevLett.103.237001; citation_id=CR21

citation_journal_title=Phys. Rev. B; citation_title=Non-abelian quantum order in spin–orbit-coupled semiconductors: The search for topological Majorana particles in solid state systems; citation_author=JD Sau, S Tewari, R Lutchyn, T Stanescu, SD Sarma; citation_volume=82; citation_publication_date=2010; citation_pages=214509; citation_doi=10.1103/PhysRevB.82.214509; citation_id=CR22

citation_journal_title=Phys. Rev. B; citation_title=Proximity-induced superconductivity in topological Bi2Te2Se and Bi2Se3 films: Robust zero-energy bound state possibly due to Majorana fermions; citation_author=G Koren, T Kirzhner, E Lahoud, KB Chashka, A Kanigel; citation_volume=84; citation_publication_date=2011; citation_pages=224521; citation_doi=10.1103/PhysRevB.84.224521; citation_id=CR23

citation_journal_title=Science; citation_title=Signatures of Majorana fermions in hybrid superconductor–semiconductor nanowire devices; citation_author=V Mourik; citation_volume=336; citation_publication_date=2012; citation_pages=1003-1007; citation_doi=10.1126/science.1222360; citation_id=CR24

Deng, M. T. et al. Observation of Majorana fermions in a Nb-InSb nanowire-Nb hybrid quantum device. Preprint at http://arxiv.org/abs/1204.4130  (2012).

citation_journal_title=Nature; citation_title=Kondo effect in a single-electron transistor; citation_author=D Goldhaber-Gordon; citation_volume=391; citation_publication_date=1998; citation_pages=156-159; citation_doi=10.1038/34373; citation_id=CR26

citation_journal_title=Phys. Rev. B; citation_title=Kondo-like zero-bias anomaly in electronic transport through an ultrasmall Si quantum dot; citation_author=LP Rokhinson, LJ Guo, SY Chou, DC Tsui; citation_volume=60; citation_publication_date=1999; citation_pages=R16319-R16321; citation_doi=10.1103/PhysRevB.60.R16319; citation_id=CR27

citation_journal_title=Phys. Rev. Lett.; citation_title=Low-temperature fate of the 0.7 structure in a point contact: A Kondo-like correlated state in an open system; citation_author=SM Cronenwett; citation_volume=88; citation_publication_date=2002; citation_pages=226805; citation_doi=10.1103/PhysRevLett.88.226805; citation_id=CR28

citation_journal_title=Phys. Rev. Lett.; citation_title=Spontaneous spin polarization in quantum point contacts; citation_author=L Rokhinson, L Pfeiffer, K West; citation_volume=96; citation_publication_date=2006; citation_pages=156602; citation_doi=10.1103/PhysRevLett.96.156602; citation_id=CR29

citation_journal_title=Eur. Phys. J. B; citation_title=Fractional a.c. Josephson effect in p- and d-wave superconductors; citation_author=H-J Kwon, K Sengupta, V Yakovenko; citation_volume=37; citation_publication_date=2003; citation_pages=349-361; citation_doi=10.1140/epjb/e2004-00066-4; citation_id=CR30

citation_journal_title=Phys. Rev. B; citation_title=Josephson current and noise at a superconductor/quantum-spin-Hall-insulator/superconductor junction; citation_author=L Fu, CL Kane; citation_volume=79; citation_publication_date=2009; citation_pages=161408; citation_doi=10.1103/PhysRevB.79.161408; citation_id=CR31

citation_journal_title=Phys. Rev. Lett.; citation_title=Quantized conductance at the Majorana phase transition in a disordered superconducting wire; citation_author=AR Akhmerov, JP Dahlhaus, F Hassler, M Wimmer, CWJ Beenakker; citation_volume=106; citation_publication_date=2011; citation_pages=057001; citation_doi=10.1103/PhysRevLett.106.057001; citation_id=CR32

citation_journal_title=Phys. Rev. B; citation_title=Experimental and materials considerations for the topological superconducting state in electron and hole doped semiconductors: searching for non-Abelian Majorana modes in 1D nanowires and 2D heterostructures; citation_author=JD Sau, S Tewari, S Das Sarma; citation_volume=85; citation_publication_date=2012; citation_pages=064512; citation_doi=10.1103/PhysRevB.85.064512; citation_id=CR33

citation_title=Introduction to Superconductivity; citation_publication_date=1996; citation_id=CR34; citation_author=M Tinkham

citation_journal_title=Zh. Eksp. Teor. Fiz.; citation_title=Thermal conductivity of the intermediate state of superconductors; citation_author=A Andreev; citation_volume=46; citation_publication_date=1964; citation_pages=1823-1828; citation_id=CR35

citation_journal_title=Science; citation_title=Tunable supercurrent through semiconductor nanowires; citation_author=Y-J Doh; citation_volume=309; citation_publication_date=2005; citation_pages=272-275; citation_doi=10.1126/science.1113523; citation_id=CR36

citation_journal_title=Phys. Rev. Lett.; citation_title=Josephson currents in superconducting tunnelling: The effect of microwaves and other observations; citation_author=S Shapiro; citation_volume=11; citation_publication_date=1963; citation_pages=80-82; citation_doi=10.1103/PhysRevLett.11.80; citation_id=CR37

citation_title=Dynamics of Josephson Junctions and Circuits; citation_publication_date=1984; citation_id=CR38; citation_author=KK Likharev

citation_journal_title=Phys. Rev. Lett.; citation_title=Unconventional Josephson signatures of Majorana bound states; citation_author=L Jiang; citation_volume=107; citation_publication_date=2011; citation_pages=236401; citation_doi=10.1103/PhysRevLett.107.236401; citation_id=CR39

Pikulin, D. I. & Nazarov, Y. V. Phenomenology and dynamics of Majorana Josephson junction. Preprint at http://arxiv.org/abs/1112.6368  (2011).

citation_journal_title=Phys. Rev. Lett.; citation_title=AC Josephson effect in finite-length nanowire junctions with Majorana modes; citation_author=P San-Jose, E Prada, R Aguado; citation_volume=108; citation_publication_date=2011; citation_pages=257001; citation_doi=10.1103/PhysRevLett.108.257001; citation_id=CR41

Domínguez, F., Hassler, F. & Platero, G. On the dynamical detection of Majorana fermions in current-biased nanowires. Preprint at http://arxiv.org/abs/1202.0642  (2012).

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Nature Physics

Tập 8 Số 11

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