Within the effective-mass and finite-height potential barrier approximation,a theoretical study of the effects of strain and hydrostatic pressure on the exciton emission wavelength and electron-hole recombination rate in wurtzite cylindrical GaN/AlxGa1-xN quantum dots (QDs) is performed using a variational approach.Numerical results show that the emission wavelength with strain effect is higher than that without strain effect when the QD height is large (＞ 3.8 nm),but the status is opposite when the QD height is small (＜ 3.8 nm).The height of GaN QDs must be less than 5.5 nm for an efficient electron-hole recombination process due to the strain effect.The emission wavelength decreases linearly and the electron-hole recombination rate increases almost linearly with applied hydrostatic pressure.The hydrostatic pressure has a remarkable influence on the emission wavelength for large QDs,and has a significant influence on the electron-hole recombination rate for small QDs.Furthermore,the present numerical outcomes are in qualitative agreement with previous experimental findings under zero pressure.
参考文献
| [1] | Nakamura S,Chichibu S F.Introduction to nitride semiconductor blue lasers and light emitting diodes.London:Taylor & Francis,2000 |
| [2] | Mukai T,Narimatsu H,Nakamura S.Amber InGaN-based lightemitting diodes operable at high ambient temperatures.Jpn J Appl Phys Ⅱ,1998,37:L479 |
| [3] | Akasaki I,Sota S,Sakai H,et al.Shortest wavelength semiconductor laser diode.Electron Lett,1996,32:1105 |
| [4] | Nakamura S,Senoh M,Nagahama S,et al.Violet InGaN/ GaN/AlGaN-based laser diodes operable at 50 ℃ with a fundamental transverse mode.Jpn J Appl Phys Ⅱ,1999,38:L226 |
| [5] | Bernardini F Fiorentini V.Electronic dielectric constants of insulators calculated by the polarization method.Phys Rev B,1998,58:15292 |
| [6] | Bemardini F,Fiorentini V,Vanderbilt D.Polarization-based calculation of the dielectric tensor of polar crystals.Phys Rev Lett,1997,79:3958 |
| [7] | Fonoberov V A,Balandin A A.Excitonic properties of strained wurtzite and zinc-blende GaN/AlxGa1-xN quantum dots.J Appl Phys,2003,94:7178 |
| [8] | Bretagnon T,Kalliakos S,Lefebvre P,et al.Time dependence of the photoluminescence of GaN/AIN quantum dots under high photoexcitation.Phys Rev B,2003,68:205301 |
| [9] | De Rinaldis S,Amico I D,Rossi F.Intrinsic electric field effects on few-particle interactions in coupled GaN quantum dots.Phys Rev B,2004,69:235316 |
| [10] | Dai X Q,Huang F Z,Zheng D M.Influence of Al content on exciton confined in GaN/AlxGa1-xN quantum dots.Chinese Journal of Semiconductors,2005,26:697 (in Chinese) |
| [11] | Zheng D M,Dai X Q.Exciton states confined in strained GaN/AlxGa1-xN quantum dots.Journal of Huaibei Coal Industry Teachers College (Natural Science Edition),2006,27:31 (in Chinese) |
| [12] | Ha S H,Ban S L.Binding energies of screened excitons in a strained (111)-oriented Zinc-blend GaN/AlGaN quantum well under hydrostatic pressure.Journal of Semiconductors,2008,29:234 |
| [13] | Zhang M,Ban S L.Pressure influence on bound polarons in a strained wurtzite GaN/AlxGa1-xN heterojunction under an electric field.Journal of Semiconductors,2010,31:052002 |
| [14] | Wagner J M,Bechstedt F.Pressure dependence of the dielectric and lattice-dynamical properties of GaN and AIN.Phys Rev B,2000,62:4526 |
| [15] | Gofii A R,Siegle H,Syassen K,et al.Effect of pressure on optical phonon modes and transverse effective charges in GaN and AIN.Phys Rev B,2001,64:035205 |
| [16] | Lpkowski S P,Teisseyre H,Suski T,et al.Piezoelectric field and its influence on the pressure behavior of the light emission from GaN/AlGaN strained quantum wells.Appl Phys Lett,2001,79:1483 |
| [17] | Ha S H,Ban S L.Binding energies of excitons in a strained wurtzite GaN/AlGaN quantum well influenced by screening and hydrostatic pressure.J Phys:Condens Matter,2008,20:085218 |
| [18] | Xia C X,Wei S Y,Zhao X.Built-in electric field effect on hydrogenic impurity in wurtzite GaN/AlGaN quantum dot.Appl Surf Sci,2007,253:5345 |
| [19] | Ramvall P,Tanaka S,Nomura S,et al.Observation of confinement-dependent exciton binding energy of GaN quantum dots.Appl Phys Lett,1998,73:1104 |
| [20] | Shi J J,Gan Z Z.Effects op piezoelectricity and spontaneous polarization on localized excitons in self-formed InGaN quantum dots.J Appl Phys,2003,94:407 |
| [21] | Szafran B,Bednarek S,Adamowski J.Parity symmetry and energy spectrum of excitons in coupled self-assembled quantum dots.Phys Rev B,2001,64:125301 |
| [22] | Li S S,Xia J B,Yuan Z L,et al.Effective-mass theory for InAs/GaAs strained coupled quantum dots.Phys Rev B,1996,54:11575 |
| [23] | Shan W,Hauenstein R J,Fischer A J,et al.Strain effects on excitonic transitions in GaN:deformation potentials.Phys Rev B,1996,54:13460 |
| [24] | Wagner M,Bechstedt F Properties of strained wurtzite GaN and AIN:ab initio studies.Phys Rev B,2002,66:115202 |
| [25] | Perlin P Mattos L,Shapiro N A,et al.Reduction of the energy gap pressure coefficient of GaN due to the constraining presence of the sapphire substrate.J Appl Phys,1999,85:2385 |
| [26] | Ting D Z Y,Chang Y C.Γ-X mixing in GaAs/AlxGa1-xAs and AlxGa1-xAs/AlAs superlattices.Phys Rev B,1987,36:4359 |
| [27] | Holtz M,Seon M,Brafman O,et al.Pressure dependence of the optic phonon energies in AlxGa1-xAs.Phys Rev B,1996,54:8714 |
| [28] | Goni A R,Syassen K,Cardona M.Effect of pressure on the refractive index of Ge and GaAs.Phys Rev B,1990,41:10104 |
| [29] | Vaschenko G,Patel D,Menoni C S,et al.Significant strain dependence of piezoelectric constants in InxGa1-xN/GaN quantum wells.Phys Rev B,2001,64:241308 |
| [30] | Raigoza N,Duque C A,Porras-Montenegro N,et al.Correlated electron hole transition energies in quantum-well wires:effects of hydrostatic pressure.Physica B,2006,371:153 |
| [31] | Vurgaftman I,Meyer J R,Ram-Mohan L R.Band parameters for Ⅲ-Ⅴ compound semiconductors and their alloys.J Appl Phys,2001,89:5815 |
| [32] | Park S H,Chuang S L.Comparison of zinc-blende and wurtzite GaN semiconductors with spontaneous polarization and piezoelectric field effects.J Appl Phys,2000,87:353 |
| [33] | Bernardini F,Fiorentini V,Vanderbilt D.Spontaneous polarization and piezoelectric constants of Ⅲ-Ⅴ nitrides.Phys Rev B,1997,56:R10024 |
| [34] | Wei S H,Zunger A.Predicted band-gap pressure coefficient of all diamond and zinc-blende semiconductors:chemical trends.Phys Rev B,1999,60:5404 |
| [35] | Tanaka S,Lee J S,Ramvall P,et al.A UV light-emitting diode incorporating GaN quantum dots.Jpn J Appl Phys,2003,42:L885 |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%