Valleytronics

Valleytronics (from valley and electronics) is an experimental area in semiconductors that exploits local extrema ("valleys") in the electronic band structure. Certain semiconductors have multiple "valleys" in the electronic band structure of the first Brillouin zone, and are known as multivalley semiconductors.^[1]^[2] Valleytronics is the technology of control over the valley degree of freedom, a local maximum/minimum on the valence/conduction band, of such multivalley semiconductors.

Details

The term was coined in analogy to spintronics. While in spintronics the internal degree of freedom of spin is harnessed to store, manipulate and read out bits of information, the proposal for valleytronics is to perform similar tasks using the multiple extrema of the band structure, so that the information of 0s and 1s would be stored as different discrete values of the crystal momentum.

Valleytronics may refer to other forms of quantum manipulation of valleys in semiconductors, including quantum computation with valley-based qubits,^[3]^[4]^[5]^[6] valley blockade and other forms of quantum electronics. First experimental evidence of valley blockade predicted in Ref.^[7] (which completes the set of Coulomb charge blockade and Pauli spin blockade) has been observed in a single atom doped silicon transistor.^[8]

Several theoretical proposals and experiments were performed in a variety of systems, such as graphene,^[9] ^[10] ^[11] few-layer phosphorene,^[12] some transition metal dichalcogenide monolayers,^[13]^[14]^[15] diamond,^[16] bismuth,^[17] silicon,^[4]^[18]^[19] carbon nanotubes,^[6] aluminium arsenide^[20] and silicene.^[21]

References

^ Behnia, Kamran (2012-07-01). "Polarized light boosts valleytronics". Nature Nanotechnology. 7 (8): 488–489. Bibcode:2012NatNa...7..488B. doi:10.1038/nnano.2012.117. ISSN 1748-3387. PMID 22751224.
^ Nebel, Christoph E. (2013). "Electrons dance in diamond". Nature Materials. 12 (8): 690–691. Bibcode:2013NatMa..12..690N. doi:10.1038/nmat3724. ISSN 1476-1122. PMID 23877395.
^ Gunawan, O.; Habib, B.; De Poortere, E. P.; Shayegan, M. (2006-10-30). "Quantized conductance in an AlAs two-dimensional electron system quantum point contact". Physical Review B. 74 (15): 155436. arXiv:cond-mat/0606272. Bibcode:2006PhRvB..74o5436G. doi:10.1103/PhysRevB.74.155436. S2CID 119086726.
^ ^a ^b Culcer, Dimitrie; et al. (2012). "Valley-Based Noise-Resistant Quantum Computation Using Si Quantum Dots". Physical Review Letters. 108 (12): 126804. arXiv:1107.0003. Bibcode:2012PhRvL.108l6804C. doi:10.1103/PhysRevLett.108.126804. PMID 22540611. S2CID 22859674.
^ "Universal quantum computing with spin and valley states". Niklas Rohling and Guido Burkard. New J. Phys. 14, 083008(2012).
^ ^a ^b "A valley–spin qubit in a carbon nanotube". E. A. Laird, F. Pei & L. P. Kouwenhoven. Nature Nanotechnology 8, 565–568 (2013).
^ Prati, Enrico (2011-10-01). "Valley Blockade Quantum Switching in Silicon Nanostructures". Journal of Nanoscience and Nanotechnology. 11 (10): 8522–8526. arXiv:1203.5368. doi:10.1166/jnn.2011.4957. ISSN 1533-4880. PMID 22400218. S2CID 28847674.
^ Crippa A; et al. (2015). "Valley blockade and multielectron spin-valley Kondo effect in silicon". Physical Review B. 92 (3): 035424. arXiv:1501.02665. Bibcode:2015PhRvB..92c5424C. doi:10.1103/PhysRevB.92.035424. S2CID 117310207.
^ A. Rycerz; et al. (2007). "Valley filter and valley valve in graphene". Nature Physics. 3 (3): 172–175. arXiv:cond-mat/0608533. Bibcode:2007NatPh...3..172R. doi:10.1038/nphys547. S2CID 119377206.
^ Mrudul, M.S.; Galan, A.J.; Ivanov, M.; Dixit, G. (2021). "Light-induced valleytronics in pristine graphene". Optica. 8 (3): 422–427. arXiv:2011.04973. Bibcode:2021Optic...8..422M. doi:10.1364/OPTICA.418152. S2CID 226289990.
^ Rana, N.; Dixit, G. (2023). "All-optical ultrafast valley switching in two-dimensional materials". Physical Review Applied. 19 (3): 034056. arXiv:2306.02856. Bibcode:2023PhRvP..19c4056R. doi:10.1103/PhysRevApplied.19.034056. S2CID 257614105.
^ Ang, Y.S.; Yang, S.A.; Zhang, C.; Ma, Z.S.; Ang, L.K. (2017). "Valleytronics in merging Dirac cones: All-electric-controlled valley filter, valve, and universal reversible logic gate". Physical Review B. 96 (24): 245410. arXiv:1711.05906. Bibcode:2017PhRvB..96x5410A. doi:10.1103/PhysRevB.96.245410. S2CID 51933139.
^ "Valley polarization in MoS2 monolayers by optical pumping". Hualing Zeng, Junfeng Dai, Wang Yao, Di Xiao and Xiaodong Cui. Nature Nanotechnology 7, 490–493 (2012).
^ Wu, Zefei; Zhou, Benjamin T.; Cai, Xiangbin; Cheung, Patrick; Liu, Gui-Bin; Huang, Meizhen; Lin, Jiangxiazi; Han, Tianyi; An, Liheng; Wang, Yuanwei; Xu, Shuigang; Long, Gen; Cheng, Chun; Law, Kam Tuen; Zhang, Fan (2019-02-05). "Intrinsic valley Hall transport in atomically thin MoS2". Nature Communications. 10 (1): 611. doi:10.1038/s41467-019-08629-9. ISSN 2041-1723. PMC 6363770. PMID 30723283.
^ Bussolotti, Fabio; Kawai, Hiroyo; Ooi, Zi En; Chellappan, Vijila; Thian, Dickson; Pang, Ai Lin Christina; Goh, Kuan Eng Johnson (2018). "Roadmap on finding chiral valleys: screening 2D materials for valleytronics". Nano Futures. 2 (3): 032001. Bibcode:2018NanoF...2c2001B. doi:10.1088/2399-1984/aac9d7. S2CID 139826293.
^ "Generation, transport and detection of valley-polarized electrons in diamond". Jan Isberg, Markus Gabrysch, Johan Hammersberg, Saman Majdi, Kiran Kumar Kovi and Daniel J. Twitchen. Nature Materials 12, 760–764 (2013). doi:10.1038/nmat3694
^ "Field-induced polarization of Dirac valleys in bismuth". Zengwei Zhu, Aurélie Collaudin, Benoît Fauqué, Woun Kang and Kamran Behnia. Nature Physics 8, 89-94 (2011).
^ Takashina, K. (2006). "Valley Polarization in Si(100) at Zero Magnetic Field". Physical Review Letters. 96 (23): 236801. arXiv:cond-mat/0604118. Bibcode:2006PhRvL..96w6801T. doi:10.1103/PhysRevLett.96.236801. PMID 16803388. S2CID 42747323.
^ Yang, C. H.; Rossi, A.; Ruskov, R.; Lai, N. S.; Mohiyaddin, F. A.; Lee, S.; Tahan, C.; Klimeck, G.; Morello, A. (2013-06-27). "Spin-valley lifetimes in a silicon quantum dot with tunable valley splitting". Nature Communications. 4: 2069. arXiv:1302.0983. Bibcode:2013NatCo...4.2069Y. doi:10.1038/ncomms3069. ISSN 2041-1723. PMID 23804134. S2CID 13978092.
^ "AlAs two-dimensional electrons in an antidot lattice: Electron pinball with elliptical Fermi contours". O. Gunawan, E. P. De Poortere, and M. Shayegan. Phys. Rev. B 75, 081304(R)(2007).
^ "Spin valleytronics in silicene: Quantum spin Hall–quantum anomalous Hall insulators and single-valley semimetals". Motohiko Ezawa, Phys. Rev. B 87, 155415 (2013)