Lithuanian Journal of Physics article / Lietuvos fizikos žurnalo straipsnis

EFROS–SHKLOVSKII HOPPING IN THE ELECTRONIC TRANSPORT IN 2D p-GaAs
Said Dlimi^a, Lhoussine Limouny^a, Jamal Hemine^b, Adil Echchelh^c, and Abdelhamid El kaaouachi^a
^aPhysics Department, Faculty of Sciences, University Ibn Zohr, B. P 8106, Hay Dakhla, 80000 Agadir, Morocco
^bLaboratoire des systèmes électroniques, traitement de l’information, mécanique et énergétique, Faculté des Sciences,
Université Ibn Tofaïl, Kénitra, Morocco
^cLaboratory of Energetic Engineering and Materials, Faculty of Sciences, Ibn Tofaïl University, Kénitra, Morocco
Email: dlimi1975@gmail.com

Received 16 May 2020; revised 4 June 2020; accepted 17 June 2020

We have investigated the resistivity of a 2D hole system in GaAs in the temperature range 200 mK < T < 800 mK at zero magnetic field and low hole densities when the system is near the metal–insulator transition in the insulating side. We have found that the resistivity follows the Efros–Shklovskii variable range hopping (ES-VRH) law, this behaviour is consistent with the existence of a Coulomb gap. The resistivity scales with temperature and the prefactor has been found independent of temperature and density, thus confirming the dominance of hole–hole interaction.

Keywords: Coulomb gap, variable range hopping, 2D GaAs hole system, low temperature
PACS: 73.21.Fg, 73.40.−c, 73.90.+f

EFROSO IR ŠKLOVSKIO ŠOKAVIMAS ELEKTRONŲ PERNAŠOJE DVIMAČIAME p-GaAs
Said Dlimi^a, Lhoussine Limouny^a, Jamal Hemine^b, Adil Echchelh^b, Abdelhamid El kaaouachi^a

^aIbn Zohr universitetas, Agadyras, Marokas
^bIbn Tofaïl universitetas, Kenitra, Marokas

References / Nuorodos

[1] A.L. Efros and B.I. Shklovskii, Coulomb gap and low temperature conductivity of disordered systems, J. Phys. C 8, L49 (1975),
https://doi.org/10.1088/0022-3719/8/4/003
[2] N.F. Mott and E.A. Davis, Electronic Processes in Non-crystalline Materials, 2nd ed. (Clarendon Press, Oxford, 1979),
https://global.oup.com/academic/product/electronic-processes-in-non-crystalline-materials-9780199645336
[3] A.R. Hamilton, M.Y. Simmons, M. Pepper, E.H. Linfield, and D.A. Ritchie, Localisation and the metal−insulator transition in two dimensions, Physica B 296, 21−31 (2001),
https://doi.org/10.1016/S0921-4526(00)00773-0
[4] S.V. Kravchenko, W.E. Mason, G.E. Bowker, J.E. Furneaux, V.M. Pudalov, and M. D'Iorio, Scaling of an anomalous metal-insulator transition in a two-dimensional system in silicon at B=0, Phys. Rev. B 51, 7038−7045 (1996),
https://doi.org/10.1103/PhysRevB.51.7038
[5] Y. Hanein, U. Meirav, D. Shahar, C.C. Li, D.C. Tsu, and H. Shtrikman, The metallic-like conductivity of a two-dimensional hole system, Phys. Rev. Lett. 80, 1288 (1998),
https://doi.org/10.1103/PhysRevLett.80.1288
[6] S. Dlimi, A. El kaaouachi, R. Abdia, A. Narjis, G. Biskupski, J. Hemine, L. Limouny, and A. Sybous, Low temperature electrical transport properties in dilute 2D GaAs hole systems with magnetic field, AIP Conf. Proc. 1435, 385 (2012),
https://doi.org/10.1063/1.4712120
[7] N.F. Mott, Conduction in glasses containing transition metal ions, J. Non-Cryst. Solids 1, 1 (1968),
https://doi.org/10.1016/0022-3093(68)90002-1
[8] T. Ferrus, R. George, C.H.W. Barnes, N. Lumpkin, D.J. Paul, and M. Pepper, Evidence for multiple impurity bands in sodium-doped silicon MOSFETs, Phys. Rev. B 73(4), 041304(R) (2006),
https://doi.org/10.1103/PhysRevB.73.041304
[9] H. Liu, A. Pourret, and P. Guyot-Sionnest, Mott and Efros-Shklovskii variable range hopping in CdSe quantum dots films, ACS Nano 4, 5211−5216 (2010),
https://doi.org/10.1021/nn101376u
[10] S. Dlimi, A. El kaaouachi, A. Narjis, L. Limouny, A. Sybous, and M. Errai, Hopping energy and percolation-type transport in p-GaAs low densities near the 2D metal−insulator transition at zero magnetic field, J. Phys. Chem. Solids 74, 1349−1354 (2013),
https://doi.org/10.1016/j.jpcs.2013.05.004
[11] W. Mason, S.V. Kravchenko, G.E. Bowker, and J.E. Furneaux, Experimental evidence for a Coulomb gap in two dimensions, Phys. Rev. B 52, 7857 (1995),
https://doi.org/10.1103/PhysRevB.52.7857
[12] W. Mason, S.V. Kravchenko, and J.E. Furneaux, Experimental evidence of the Coulomb gap in a high-mobility 2D electron system in silicon, Surf. Sci. 361/362, 953 (1996)
https://doi.org/10.1016/0039-6028(96)00572-9
[13] K.M. Mertes, D. Simonian, M.P. Sarachik, S.V. Kravchenko, and M. Klapwijk, Response to parallel magnetic field of a dilute two-dimensional electron system across the metal-insulator transition, Phys. Rev. B 60, R5093 (1999),
https://doi.org/10.1103/PhysRevB.60.R5093
[14] P.T. Coleridge, R.L. Williams, Y. Feng, and P. Zawadzki, Metal-insulator transition at B = 0 in p-type SiGe, Phys, Rev. B 56, R12764 (1997),
https://doi.org/10.1103/PhysRevB.56.R12764
[15] M.Y. Simmons, A.R. Hamilton, M. Pepper, E.H. Linfield, P.D. Rose, D.A. Ritchie, A.K. Savchenko, and T.G. Griffiths, Metal-insulator transition at B=0 in a dilute two dimensional GaAs-AlGaAs hole gas, Phys. Rev. Lett. 80, 1292 (1998),
https://doi.org/10.1103/PhysRevLett.80.1292
[16] S.I. Khondaker, I.S. Shlimak, J.T. Nicholls, M. Pepper, and D.A. Ritchie, Two-dimensional hopping conductivity in a δ-doped GaAs/Al_xGa_1−xAs heterostructure, Phys. Rev. B 59, 4580 (1999),
https://doi.org/10.1103/PhysRevB.59.4580
[17] A. Narjis, A. El kaaouachi, L. Limouny, S. Dlimi, A. Sybous, J. Hemine, R. Abdia, and G. Biskupski, Study of insulating electrical conductivity in hydrogenated amorphous silicon−nickel alloys at very low temperature, Physica B 406, 4155−4158 (2011),
https://doi.org/10.1016/j.physb.2011.08.021
[18] L. Limouny, A. El kaaouachi, R. Abdia, A. Narjis, G. Biskupski, J. Hemine, A. Sybous, and S. Dlimi, Study of electrical resistivity in 2D Si-MOSFETS at very low temperature, AIP Conf. Proc. 1435, 401−408 (2012),
https://doi.org/10.1063/1.4712122
[19] S. Dlimi, A. El kaaouachi, and A. Narjis, Density inhomogeneity driven metal−insulator transition in 2D p-GaAs, Physica E 54, 181−184 (2013),
https://doi.org/10.1016/j.physe.2013.07.001
[20] S. Dlimi, A. El kaaouachi, A. Narjis, L. Limouny, A. Sybous, M. Errai, and G. Biskupski, Evidence for the correlated hopping mechanism in p-GaAs near the 2D MIT at B=0T, J. Optoelectron. Adv. Mater. 15(11−12), 1222−1227 (2013),
https://joam.inoe.ro/articles/evidence-for-the-correlated-hopping-mechanism-in-p-gaas-near-the-2d-mit-at-b0t/