Conventional and microwave-modulated Shubnikov-de Haas oscillations in GaN electron systems

J. R. Juang, D. R. Hang, Tsai Yu Huang, W. K. Hung, Y. F. Chen, Gil Ho Kim, Ming Gu Lin, Tse Ming Chen, C. T. Liang, Y. Lee, Jae Hoon Lee, Jung Hee Lee

Research output: Contribution to journalConference article

2 Citations (Scopus)

Abstract

We report the drastic enhancement of Shubnikov-de Haas (SdH) oscillations observed in a GaN/AlGaN heterostructure by microwave modulation. The dependence of the SdH pattern on microwave power and temperature are investigated. The underlying mechanism is attributed to the effect of carrier heating. This technique has the advantage of keeping the carrier concentration fixed and not requiring expensive high-energy laser facilities compared with carrier-modulated SdH measurements. Moreover, we have investigated the low-temperature transport properties of front-gated Al0.18Ga 0.82N/GaN heterostructures. By changing the applied gate voltage, we can vary the carrier density in our sample. At high carrier densities (n > 4.65 × 1012 cm-2), the measured mobility (μ) is found to be a decreasing function of carrier density as μ∼n -0.31. Loss of mobility with increasing carrier density is dominated by interface roughness scattering. At low carrier densities (n < 4.24 × 1012 cm-2), the measured mobility is found to be an increasing function of carrier density as μ∼n0.34. This is consistent with remote ionized impurity scattering, although the measured exponent 0.34 is smaller than the typical value (0.7-1.5) observed in an AlGaN/GaN electron system. A possible reason is that our sample mobility is approximately five times lower than those in other devices for a similar electron density.

Original languageEnglish
Pages (from-to)631-635
Number of pages5
JournalPhysica E: Low-Dimensional Systems and Nanostructures
Volume21
Issue number2-4
DOIs
Publication statusPublished - 2004 Mar 1
EventProceedings of the Eleventh International Conference on Modulation (MSS11) - Nara, Japan
Duration: 2003 Jul 142003 Jul 18

Fingerprint

Carrier concentration
Microwaves
microwaves
oscillations
Electrons
electrons
Heterojunctions
Scattering
High energy lasers
scattering
roughness
transport properties
exponents
Transport properties
modulation
impurities
heating
augmentation
Surface roughness
Modulation

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics

Cite this

Juang, J. R. ; Hang, D. R. ; Huang, Tsai Yu ; Hung, W. K. ; Chen, Y. F. ; Kim, Gil Ho ; Lin, Ming Gu ; Chen, Tse Ming ; Liang, C. T. ; Lee, Y. ; Lee, Jae Hoon ; Lee, Jung Hee. / Conventional and microwave-modulated Shubnikov-de Haas oscillations in GaN electron systems. In: Physica E: Low-Dimensional Systems and Nanostructures. 2004 ; Vol. 21, No. 2-4. pp. 631-635.
@article{98ff4059cb9a4e29951aa4fce762c599,
title = "Conventional and microwave-modulated Shubnikov-de Haas oscillations in GaN electron systems",
abstract = "We report the drastic enhancement of Shubnikov-de Haas (SdH) oscillations observed in a GaN/AlGaN heterostructure by microwave modulation. The dependence of the SdH pattern on microwave power and temperature are investigated. The underlying mechanism is attributed to the effect of carrier heating. This technique has the advantage of keeping the carrier concentration fixed and not requiring expensive high-energy laser facilities compared with carrier-modulated SdH measurements. Moreover, we have investigated the low-temperature transport properties of front-gated Al0.18Ga 0.82N/GaN heterostructures. By changing the applied gate voltage, we can vary the carrier density in our sample. At high carrier densities (n > 4.65 × 1012 cm-2), the measured mobility (μ) is found to be a decreasing function of carrier density as μ∼n -0.31. Loss of mobility with increasing carrier density is dominated by interface roughness scattering. At low carrier densities (n < 4.24 × 1012 cm-2), the measured mobility is found to be an increasing function of carrier density as μ∼n0.34. This is consistent with remote ionized impurity scattering, although the measured exponent 0.34 is smaller than the typical value (0.7-1.5) observed in an AlGaN/GaN electron system. A possible reason is that our sample mobility is approximately five times lower than those in other devices for a similar electron density.",
author = "Juang, {J. R.} and Hang, {D. R.} and Huang, {Tsai Yu} and Hung, {W. K.} and Chen, {Y. F.} and Kim, {Gil Ho} and Lin, {Ming Gu} and Chen, {Tse Ming} and Liang, {C. T.} and Y. Lee and Lee, {Jae Hoon} and Lee, {Jung Hee}",
year = "2004",
month = "3",
day = "1",
doi = "10.1016/j.physe.2003.11.093",
language = "English",
volume = "21",
pages = "631--635",
journal = "Physica E: Low-Dimensional Systems and Nanostructures",
issn = "1386-9477",
publisher = "Elsevier",
number = "2-4",

}

Juang, JR, Hang, DR, Huang, TY, Hung, WK, Chen, YF, Kim, GH, Lin, MG, Chen, TM, Liang, CT, Lee, Y, Lee, JH & Lee, JH 2004, 'Conventional and microwave-modulated Shubnikov-de Haas oscillations in GaN electron systems', Physica E: Low-Dimensional Systems and Nanostructures, vol. 21, no. 2-4, pp. 631-635. https://doi.org/10.1016/j.physe.2003.11.093

Conventional and microwave-modulated Shubnikov-de Haas oscillations in GaN electron systems. / Juang, J. R.; Hang, D. R.; Huang, Tsai Yu; Hung, W. K.; Chen, Y. F.; Kim, Gil Ho; Lin, Ming Gu; Chen, Tse Ming; Liang, C. T.; Lee, Y.; Lee, Jae Hoon; Lee, Jung Hee.

In: Physica E: Low-Dimensional Systems and Nanostructures, Vol. 21, No. 2-4, 01.03.2004, p. 631-635.

Research output: Contribution to journalConference article

TY - JOUR

T1 - Conventional and microwave-modulated Shubnikov-de Haas oscillations in GaN electron systems

AU - Juang, J. R.

AU - Hang, D. R.

AU - Huang, Tsai Yu

AU - Hung, W. K.

AU - Chen, Y. F.

AU - Kim, Gil Ho

AU - Lin, Ming Gu

AU - Chen, Tse Ming

AU - Liang, C. T.

AU - Lee, Y.

AU - Lee, Jae Hoon

AU - Lee, Jung Hee

PY - 2004/3/1

Y1 - 2004/3/1

N2 - We report the drastic enhancement of Shubnikov-de Haas (SdH) oscillations observed in a GaN/AlGaN heterostructure by microwave modulation. The dependence of the SdH pattern on microwave power and temperature are investigated. The underlying mechanism is attributed to the effect of carrier heating. This technique has the advantage of keeping the carrier concentration fixed and not requiring expensive high-energy laser facilities compared with carrier-modulated SdH measurements. Moreover, we have investigated the low-temperature transport properties of front-gated Al0.18Ga 0.82N/GaN heterostructures. By changing the applied gate voltage, we can vary the carrier density in our sample. At high carrier densities (n > 4.65 × 1012 cm-2), the measured mobility (μ) is found to be a decreasing function of carrier density as μ∼n -0.31. Loss of mobility with increasing carrier density is dominated by interface roughness scattering. At low carrier densities (n < 4.24 × 1012 cm-2), the measured mobility is found to be an increasing function of carrier density as μ∼n0.34. This is consistent with remote ionized impurity scattering, although the measured exponent 0.34 is smaller than the typical value (0.7-1.5) observed in an AlGaN/GaN electron system. A possible reason is that our sample mobility is approximately five times lower than those in other devices for a similar electron density.

AB - We report the drastic enhancement of Shubnikov-de Haas (SdH) oscillations observed in a GaN/AlGaN heterostructure by microwave modulation. The dependence of the SdH pattern on microwave power and temperature are investigated. The underlying mechanism is attributed to the effect of carrier heating. This technique has the advantage of keeping the carrier concentration fixed and not requiring expensive high-energy laser facilities compared with carrier-modulated SdH measurements. Moreover, we have investigated the low-temperature transport properties of front-gated Al0.18Ga 0.82N/GaN heterostructures. By changing the applied gate voltage, we can vary the carrier density in our sample. At high carrier densities (n > 4.65 × 1012 cm-2), the measured mobility (μ) is found to be a decreasing function of carrier density as μ∼n -0.31. Loss of mobility with increasing carrier density is dominated by interface roughness scattering. At low carrier densities (n < 4.24 × 1012 cm-2), the measured mobility is found to be an increasing function of carrier density as μ∼n0.34. This is consistent with remote ionized impurity scattering, although the measured exponent 0.34 is smaller than the typical value (0.7-1.5) observed in an AlGaN/GaN electron system. A possible reason is that our sample mobility is approximately five times lower than those in other devices for a similar electron density.

UR - http://www.scopus.com/inward/record.url?scp=12144286613&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=12144286613&partnerID=8YFLogxK

U2 - 10.1016/j.physe.2003.11.093

DO - 10.1016/j.physe.2003.11.093

M3 - Conference article

AN - SCOPUS:12144286613

VL - 21

SP - 631

EP - 635

JO - Physica E: Low-Dimensional Systems and Nanostructures

JF - Physica E: Low-Dimensional Systems and Nanostructures

SN - 1386-9477

IS - 2-4

ER -