Skip to main content Accessibility help
×
Home
Hostname: page-component-78dcdb465f-jxh9h Total loading time: 23.824 Render date: 2021-04-17T06:33:21.877Z Has data issue: true Feature Flags: { "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true, "metricsAbstractViews": false, "figures": false, "newCiteModal": false, "newCitedByModal": true }

Weak Antilocalization in Polarization-Doped AlGaN/GaN Heterostructures

Published online by Cambridge University Press:  01 February 2011

Nicolas Henri Thillosen
Affiliation:
n.thillosen@fz-juelich.de, Research Centre Juelich, Institute of Thin Films and Interfaces (ISG1), Leo Brand Str., Juelich, N/A, 52425, Germany, +492461612926, +492461612940
Thomas Schäpers
Affiliation:
th.schaepers@fz-juelich.de
Nicoleta Kaluza
Affiliation:
n.kaluza@fz-juelich.de
Hilde Hardtdegen
Affiliation:
h.hardtdegen@fz-juelich.de
Vitaliy Guzenko
Affiliation:
v.guzenko@fz-juelich.de
Get access

Abstract

The properties of AlGaN/GaN heterostructures have been a subject of great activity because of their application in high frequency, high power, and high temperature devices. Magnetotransport measurements give the possibility to study the properties of a two-dimensional electron gas. Indeed, Shubnikov-de Haas oscillations of a two-dimensional electron gas can be observed at high magnetic fields. Moreover, magnetoresistance measurements close to zero magnetic field give the possibility to investigate the weak localization and weak antilocalization arising from AlGaN/GaN heterostructures. The latter is related to the spin-orbit interaction on the spin of the carriers present in these heterostructures and is a key-feature of the spin-transistor proposed by Datta and Das [1]. As a matter of fact, the spin orientation between the electrodes of this novel device should be manipulated by the controllable strength of the spin-orbit interaction in the two-dimensional electron gas. In order to obtain information on spin-orbit effects in AlGaN/GaN heterostructures we therefore analyzed the weak antilocalization observed in the magnetoresistance.

Polarization-doped AlGaN/GaN heterostructures were grown by metalorganic vapor phase epitaxy (MOVPE) on the (0001) surface of sapphire substrates. First a 3 mm-thick GaN buffer layer was grown, followed by a Al0.3Ga0.7N layer with a thickness of 20 nm. Magnetotransport measurements were performed over a magnetic field range from –50 mT to +50 mT at various temperatures between 0.1 and 18 K. The Hall-bars were prepared by optical lithography and Ar+-ion-beam-etching technique. The metals used for the ohmic contacts were Ti/Al/Ni/Au. The mobility and carrier concentration in the single occupied subband were obtained from the Shubnikov-de Haas oscillations with the respective values of 9100 cm2/Vs and 6.2×1012 cm-2.

In our case, the Shubnikov-de Haas oscillations of the two-dimensional electron gas reveal the occupation of a single subband in the nearly triangular quantum well. At low magnetic field, weak localization as well as weak antilocalization were observed, showing that strong spin-orbit interaction is present in our structures. A previous report [2] explained the weak-antilocalization as being related to the intersubband scattering due to the occupation of a second subband in a modulation-doped quantum well. We show that weak antilocalization is also present in a polarization-doped quantum well with a single subband being occupied. In this perspective, temperature-dependent weak antilocalization measurements will be presented and analyzed using adequate theoretical models. Finally, the relevant scattering times like elastic scattering time, dephasing time as well as spin-orbit scattering time have been extracted. [1] S. Datta and B. Das, Appl. Phys. Lett. Vol. 56, pp. 665-667, 1990. [2] J. Lu et al., Appl. Phys. Lett., Vol. 85, pp. 3125-3127, 2004

Type
Research Article
Copyright
Copyright © Materials Research Society 2006

Access options

Get access to the full version of this content by using one of the access options below.

References

[1] Dietl, T., Ohno, H., Matsukura, F., Cibert, J., and Ferrand, D., Science 287, 1019 (2000).CrossRefGoogle Scholar
[2] Schmidt, G., Ferrand, D., Molenkamp, L.W., Filip, A.T., and van Wees, B.J., Phys. Rev. B 62, R4790 (2000).CrossRefGoogle Scholar
[3] Datta, S. and Das, B., Appl. Phys. Lett. 56, 665 (1990).CrossRefGoogle Scholar
[4] Rashba, E.I., Fiz. Tverd. Tela (Leningrad) [Sov. Phys. Solid State 2, 1109 (1960)] 2, 1224 (1960).Google Scholar
[5] Litvinov, V., Phys. Rev. B 68, 155314 (2003).CrossRefGoogle Scholar
[6] Nitta, J., Akazaki, T., Takayanagi, H., and Enoki, T., Phys. Rev. Lett. 78, 1335 (1997).CrossRefGoogle Scholar
[7] Engels, G., Lange, J., Schäpers, Th., and Lüth, H., Phys. Rev. B 55, R1958 (1997).CrossRefGoogle Scholar
[8] Koga, T., Nitta, J., Akazaki, T., and Takayanagi, H., Phys. Rev. Lett. 89, 046801/1 (2002).CrossRefGoogle Scholar
[9] Schierholz, C., Kürsten, R., Meier, G., Matsuyama, T., and Merkt, U., Phys. Stat. Sol. 233, 436444 (2002).3.0.CO;2-J>CrossRefGoogle Scholar
[10] Lo, I., Tsai, J.K., Yao, W.J., and Ho, P.C., Phys. Rev. B 65, 161306/1 (2002).CrossRefGoogle Scholar
[11] Tsubaki, K., Maeda, N., Saitoh, T., and Kobayashi, N., Appl. Phys. Lett. 80, 3126 (2002).CrossRefGoogle Scholar
[12] Lu, J., Shen, B., Tang, N., Chen, D.J., Zhao, H., Liu, D.W., Zhang, R., Shi, Y., Zheng, Y.D., Qiu, Z.J., et al. Appl. Phys. Lett. 85, 3125 (2004).CrossRefGoogle Scholar
[13] Cho, K., Huang, T.-Y., Wang, H.-S., Lin, M.-G., Chen, T.-M., Liang, C.-T., and Chen, Y.F., Appl. Phys. Lett. 86, 222102 (2005).CrossRefGoogle Scholar
[14] Dresselhaus, G., Phys. Rev. 10, 580 (1955).CrossRefGoogle Scholar
[15] Brosig, S., Ensslin, K., Warburton, R.J., Nguyen, C., Brar, B., Thomas, M., and Kroemer, H., Phys. Rev. B 60, R13989 (1999).Google Scholar
[16] Iordanskii, S.V., Lyanda-Geller, Y.B., and Pikus, G.E., JETP Lett. 60, 206 (1994)Google Scholar

Full text views

Full text views reflects PDF downloads, PDFs sent to Google Drive, Dropbox and Kindle and HTML full text views.

Total number of HTML views: 0
Total number of PDF views: 12 *
View data table for this chart

* Views captured on Cambridge Core between September 2016 - 17th April 2021. This data will be updated every 24 hours.

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Weak Antilocalization in Polarization-Doped AlGaN/GaN Heterostructures
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Weak Antilocalization in Polarization-Doped AlGaN/GaN Heterostructures
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Weak Antilocalization in Polarization-Doped AlGaN/GaN Heterostructures
Available formats
×
×

Reply to: Submit a response


Your details


Conflicting interests

Do you have any conflicting interests? *