Multiple-photon Peak Generation Near The 10 M Range In Quantum Dot Infrared Photodetectors

We present results from simulations of the photocurrent observed in recently fabricated InAs quantum dot infrared photodetectors that respond with strong resonance peaks in the ∼ 10 m wavelength range. The results are in good agreement with experimental data generated earlier. Multiphoton scattering of electrons localized in the quantum dots are not only in accordance with the observed patterns, but are also necessary to explain the photocurrent spectrum obtained in the calculations. © 2011 American Institute of Physics.1096Martyniuk, P., Rogalski, A., (2008) Prog. Quantum Electron., 32, p. 89. , For a recent review, see, 10.1016/j.pquantelec.2008.07.001Chakrabarti, S., Stiff-Roberts, A.D., Su, X.H., Bhattacharya, P., Ariyawansa, G., Perera, A.G.U., High-performance mid-infrared quantum dot infrared photodetectors (2005) Journal of Physics D: Applied Physics, 38 (13), pp. 2135-2141. , DOI 10.1088/0022-3727/38/13/009, PII S002237270592069XLim, H., Zhang, W., Tsao, S., Sills, T., Szafraniec, J., Mi, K., Movaghar, B., Razeghi, M., Quantum dot infrared photodetectors: Comparison of experiment and theory (2005) Physical Review B - Condensed Matter and Materials Physics, 72 (8), p. 085332. , http://oai.aps.org/oai/?verb=ListRecords&metadataPrefix= oai_apsmeta_2&set=journal:PRB:72, DOI 10.1103/PhysRevB.72.085332Razeghi, M., Lim, H., Tsao, S., Szafraniec, J., Zhang, W., Mi, K., Movaghar, B., Transport and photodetection in self-assembled semiconductor quantum dots (2005) Nanotechnology, 16 (2), pp. 219-229. , DOI 10.1088/0957-4484/16/2/007Pal, D., Towe, E., (2006) Appl. Phys. Lett., 88, p. 153109. , 10.1063/1.2193466Bhattacharya, P., Su, X.H., Chakrabarti, S., Ariyawansa, G., Perera, A.G.U., Characteristics of a tunneling quantum-dot infrared photodetector operating at room temperature (2005) Applied Physics Letters, 86 (19), pp. 1-3. , DOI 10.1063/1.1923766, 191106Dupont, E., Corkum, P., Liu, H.C., Wilson, P.H., Buchanan, M., Wasilewski, Z.R., (1994) Appl. Phys. Lett., 65, p. 1560. , 10.1063/1.113004Maier, T., Schneider, H., Walther, M., Koidl, P., Liu, H.C., (2004) Appl. Phys. Lett., 84, p. 5162. , 10.1063/1.1763978Jiang, J., Fu, Y., Li, N., Chen, X.S., Zhen, H.L., Lu, W., Wang, M.K., Li, Y.G., (2004) Appl. Phys. Lett., 85, p. 3614. , 10.1063/1.1781732Aivaliotis, P., Zibik, E.A., Wilson, L.R., Cockburn, J.W., Hopkinson, M., Vinh, N.Q., (2008) Appl. Phys. Lett., 92, p. 023501. , 10.1063/1.2833691Sirtori, C., Capasso, F., Sivco, D.L., Cho, A.Y., (1992) Appl. Phys. Lett., 60, p. 2678. , 10.1063/1.106893Souza, P.L., Lopes, A.J., Gebhard, T., Unterrainer, K., Pires, M.P., Villas-Boas, J.M., Vieira, G.S., Studart, N., Quantum dot structures grown on Al containing quaternary material for infrared photodetection beyond 10 μm (2007) Applied Physics Letters, 90 (17), p. 173510. , DOI 10.1063/1.2733603Gebhard, T., Alvarenga, D., Souza, P.L., Guimares, P.S.S., Unterrainer, K., Pires, M.P., Vieira, G.S., Villas-Boas, J.M., (2008) Applied Phys. Lett., 93, p. 052103. , 10.1063/1.2965804Pryor, C.E., Pistol, M.-E., Band-edge diagrams for strained III-V semiconductor quantum wells, wires, and dots (2005) Physical Review B - Condensed Matter and Materials Physics, 72 (20), pp. 1-11. , http://oai.aps.org/oai/?verb=ListRecords&metadataPrefix= oai_apsmeta_2&set=journal:PRB:72, DOI 10.1103/PhysRevB.72.205311, 205311Degani, M.H., Maialle, M.Z., (2010) J. Comput. Theor. Nanosci., 7, p. 454. , 10.1166/jctn.2010.1380Feit, M.D., Fleck Jr., J.A., Steiger, A., (1982) J. Comput. Phys., 47, p. 412. , 10.1016/0021-9991(82)90091-2Degani, M.H., (1991) Appl. Phys. Lett., 59, p. 57(2002) Phys. Rev. B, 66, p. 23306. , 10.1063/1.105521Maialle, M.Z., Degani, M.H., Madureira, J.R., Farinas, P.F., (2009) J. Appl. Phys., 106, p. 123703. , 10.1063/1.3270263Fano, U., Cooper, J.W., (1968) Rev. Mod. Phys., 40, p. 441. , 10.1103/RevModPhys.40.441Tsolakidis, A., Snchez-Portal, D., Martin, R.M., (2002) Phys. Rev. B, 66, p. 235416. , 10.1103/PhysRevB.66.23541

Electron spin relaxation by nuclei in semiconductor quantum dots

We have studied theoretically the electron spin relaxation in semiconductor quantum dots via interaction with nuclear spins. The relaxation is shown to be determined by three processes: (i) -- the precession of the electron spin in the hyperfine field of the frozen fluctuation of the nuclear spins; (ii) -- the precession of the nuclear spins in the hyperfine field of the electron; and (iii) -- the precession of the nuclear spin in the dipole field of its nuclear neighbors. In external magnetic fields the relaxation of electron spins directed along the magnetic field is suppressed. Electron spins directed transverse to the magnetic field relax completely in a time on the order of the precession period of its spin in the field of the frozen fluctuation of the nuclear spins. Comparison with experiment shows that the hyperfine interaction with nuclei may be the dominant mechanism of electron spin relaxation in quantum dots

Exciton spin relaxation in single semiconductor quantum dots

We study the relaxation of the exciton spin (longitudinal relaxation time $T_{1}$) in single asymmetrical quantum dots due to an interplay of the short--range exchange interaction and acoustic phonon deformation. The calculated relaxation rates are found to depend strongly on the dot size, magnetic field and temperature. For typical quantum dots and temperatures below 100 K, the zero--magnetic field relaxation times are long compared to the exciton lifetime, yet they are strongly reduced in high magnetic fields. We discuss explicitly quantum dots based on (In,Ga)As and (Cd,Zn)Se semiconductor compounds.Comment: accepted for Phys. Rev.

Spin splitting in a polarized quasi-two-dimensional exciton gas

We have observed a large spin splitting between "spin" $+1$ and $-1$ heavy-hole excitons, having unbalanced populations, in undoped GaAs/AlAs quantum wells in the absence of any external magnetic field. Time-resolved photoluminescence spectroscopy, under excitation with circularly polarized light, reveals that, for high excitonic density and short times after the pulsed excitation, the emission from majority excitons lies above that of minority ones. The amount of the splitting, which can be as large as 50% of the binding energy, increases with excitonic density and presents a time evolution closely connected with the degree of polarization of the luminescence. Our results are interpreted on the light of a recently developed model, which shows that, while intra-excitonic exchange interaction is responsible for the spin relaxation processes, exciton-exciton interaction produces a breaking of the spin degeneracy in two-dimensional semiconductors.Comment: Revtex, four pages; four figures, postscript file Accepted for publication in Physical Review B (Rapid Commun.

Signatures of the excitonic memory effects in four-wave mixing processes in cavity polaritons

We report the signatures of the exciton correlation effects with finite memory time in frequency domain degenerate four-wave mixing (DFWM) in semiconductor microcavity. By utilizing the polarization selection rules, we discriminate instantaneous, mean field interactions between excitons with the same spins, long-living correlation due to the formation of biexciton state by excitons with opposite spins, and short-memory correlation effects in the continuum of unbound two-exciton states. The DFWM spectra give us the relative contributions of these effects and the upper limit for the time of the exciton-exciton correlation in the unbound two-exciton continuum. The obtained results reveal the basis of the cavity polariton scattering model for the DFWM processes in high-Q GaAs microcavity.Comment: 11 pages, 1 figur

Steady states of a chi-three parametric oscillator with coupled polarisations

Polarisation effects in the microcavity parametric oscillator are studied using a simple model in which two chi-three optical parametric oscillators are coupled together. It is found that there are, in general, a number of steady states of the model under continuous pumping. There are both continuous and discontinuous thresholds, at which new steady-states appear as the driving intensity is increased: at the continuous thresholds, the new state has zero output intensity, whereas at the discontinuous threshold it has a finite output intensity. The discontinuous thresholds have no analog in the uncoupled device. The coupling also generates rotations of the linear polarisation of the output compared with the pump, and shifts in the output frequencies as the driving polarisation or intensity is varied. For large ratios of the interaction between polarisations to the interaction within polarisations, of the order of 5, one of the thresholds has its lowest value when the pump is elliptically polarised. This is consistent with recent experiments in which the maximum output was achieved with an elliptically polarised pump.Comment: 7 pages, 4 figure

Polarized interacting exciton gas in quantum wells and bulk semiconductors

We develop a theory to calculate exciton binding energies of both two- and three-dimensional spin polarized exciton gases within a mean field approach. Our method allows the analysis of recent experiments showing the importance of the polarization and intensity of the excitation light on the exciton luminescence of GaAs quantum wells. We study the breaking of the spin degeneracy observed at high exciton density $(5 \ \ 10^{10} cm ^2)$. Energy level splitting betwen spin +1 and spin -1 is shown to be due to many-body inter-excitonic exchange while the spin relaxation time is controlled by intra-exciton exchange.Comment: Revtex, 4 figures sent by fax upon request by e-mai

Exciton Spin Dynamics in Semiconductor Quantum Wells

In this paper we will review Exciton Spin Dynamics in Semiconductor Quantum Wells. The spin properties of excitons in nanostructures are determined by their fine structure. We will mainly focus in this review on GaAs and InGaAs quantum wells which are model systems.Comment: 55 pages, 27 figure

Coherent Population Trapping In Intersubband Photocurrent Spectra

We present results from numerical simulations of the photocurrent generated by intersubband optical transitions in a double quantum well coupled with a continuum of extended states. The photocurrent spectra are obtained directly from the time-dependent Schrödinger equation for the coherent regime without any adjusting parameters in the calculations other than the ones that define the physical system, also in a nonperturbative way and without basis-set expansions or truncations. A realistic representation of a three-level system in the Lambda ("Λ") configuration is investigated when two bound states in each quantum well are coupled by exciting fields via an excited quasibound state. Resonance between the exciting fields and the quantum states leads to coherent effects such as Rabi-dressed states, electromagnetically induced transparency, and population trapping, which are investigated in terms of the photocurrent spectral changes; that is, the coherent optical dynamics can be seen from the photocurrent signal. An excitation scheme involving two-photon absorption was proposed to produce the population-trapping effects using only one exciting field. © 2011 American Physical Society.8315Allen, L., Eberly, J.H., (1975) Optical Resonance and Two Level Atoms, , Wiley, New YorkXu, X., Sun, B., Berman, P.R., Steel, D.G., Bracker, A.S., Gammon, D., Sham, L.J., Coherent optical spectroscopy of a strongly driven quantum dot (2007) Science, 317 (5840), pp. 929-932. , DOI 10.1126/science.1142979Gerardot, B.D., Brunner, D., Dalgarno, P.A., Karrai, K., Badolato, A., Petroff, P.M., Warburton, R.J., (2009) New J. Phys., 11, p. 013028. , NJOPFM 1367-2630 10.1088/1367-2630/11/1/013028Zrenner, A., Beham, E., Stufler, S., Findeis, F., Bichler, M., Abstreiter, G., (2002) Nature (London), 418, p. 612. , NATUAS 0028-0836 10.1038/nature00912Htoon, H., Takagahara, T., Kulik, D., Baklenov, O., Holmes, Jr.A.L., Shih, C.K., (2002) Phys. Rev. Lett., 88, p. 087401. , PRLTAO 0031-9007 10.1103/PhysRevLett.88.087401Ficek, Z., Swain, S., (2005) Quantum Interference and Coherence: Theory and Experiment, , in Springer, BerlinHennessy, K., Badolato, A., Winger, M., Gerace, D., Atatüre, M., Gulde, S., Fält, S., Imamoglu, A., (2007) Nature (London), 445, p. 896. , NATUAS 0028-0836 10.1038/nature05586Laucht, A., Villas-Bôas, J.M., Stobbe, S., Hauke, N., Hofbauer, F., Böhm, G., Lodahl, P., Finley, J.J., (2010) Phys. Rev. B, 82, p. 075305. , NATUAS 1098-0121 10.1103/PhysRevB.82.075305Mukamel, S., (1995) Principles of Nonlinear Optics and Spectroscopy, , Oxford University Press, New YorkAbbarchi, M., Kuroda, T., Mano, T., Sakoda, K., Mastrandrea, C.A., Vinattieri, A., Gurioli, M., Tsuchiya, T., (2010) Phys. Rev. B, 82, p. 201301. , NATUAS 1098-0121 10.1103/PhysRevB.82.201301Dupont, E., Liu, H.C., Springthorpe, A.J., Lai, W., Extavour, M., (2003) Phys. Rev. B, 68, p. 245320. , NATUAS 1098-0121 10.1103/PhysRevB.68.245320Wu, J.-H., Gao, J.-Y., Xu, J.-H., Silvestri, L., Artoni, M., La Rocca, G.C., Bassani, F., Ultrafast all optical switching via tunable fano interference (2005) Physical Review Letters, 95 (5), pp. 1-4. , http://oai.aps.org/oai/?verb=ListRecords&metadataPrefix= oai_apsmeta_2&set=journal:PRL:95, DOI 10.1103/PhysRevLett.95.057401, 057401Falst, J., Capasso, F., Sirtori, C., West, K.W., Pfeiffer, L.N., Controlling the sign of quantum interference by tunnelling from quantum wells (1997) Nature, 390 (6660), pp. 589-591. , DOI 10.1038/37562Levine, B.F., (1993) J. Appl. Phys., 74, p. 1. , JAPIAU 0021-8979 10.1063/1.354252Maialle, M.Z., Degani, M.H., Madureira, J.R., Farinas, P.F., (2009) J. Appl. Phys., 106, p. 123703. , JAPIAU 0021-8979 10.1063/1.3270263Degani, M.H., Maialle, M.Z., (2010) J. Comput. Theor. Nanosci., 7, p. 454. , JAPIAU 1546-1955 10.1166/jctn.2010.1380Vibók, A., Balint-Kurti, G.G., (1992) J. Phys. Chem., 96, p. 8712. , JPCHAX 0022-3654 10.1021/j100201a012Neuhasuer, D., Baer, M., (1989) J. Chem. Phys., 90, p. 4351. , 0021-9606 10.1063/1.456646Ramsay, A.J., (2010) Semicond. Sci. Technol., 25, p. 103001. , SSTEET 0268-1242 10.1088/0268-1242/25/10/103001Boller, K.-J., Imamoglu, A., Harris, S.E., (1991) Phys. Rev. Lett., 66, p. 2593. , PRLTAO 0031-9007 10.1103/PhysRevLett.66.2593Schneider, H., Liu, H.C., Winnerl, S., Song, C.Y., Drachenko, O., Walther, M., Faist, J., Helm, M., (2009) Infrared Phys. Technol., 52, p. 419. , IPTEEY 1350-4495 10.1016/j.infrared.2009.05.036Zavriyev, A., Dupont, E., Corkum, P.B., Liu, H.C., Biglov, Z., (1995) Opt. Lett., 20, p. 1885. , OPLEDP 0146-9592 10.1364/OL.20.001886Degani, M.H., Maialle, M.Z., Farinas, P.F., Studart, N., Pires, M.P., Souza, P.L., (2011) J. Appl. Phys., 109, p. 064510. , 0021-8979 10.1063/1.355643

Rabi-split States Broadened By A Continuum

In this work we theoretically investigate a Λ-like three-level system. Our model consists of a onedimensional quantum well with a nearby continuum. The Λ level structure is formed by the ground state (a valence band state) and two excited states (both in conduction band), one being a localized and the other a quasi-bound state which is interacting with the continuum. An infrared (IR) field is used to drive the excited states into dressed states creating Autler-Townes doublets. We solve the semiconductor Bloch equation, in real space and in time domain, to follow the interband optical excitation dynamics. The optical absorption and the photocurrent spectra are calculated for different potential barriers separating the well and the continuum. We show how this affects the Autler-Townes doublets since this is a possible way of changing the relationship between the IR Rabi frequency and the dephasing rates. © 2013 AIP Publishing LLC.1566500501et al.,ETH Board,ETH Zurich,International Union of Pure and Applied Physics,Swiss National Science Foundation,Swiss Natl. Cent. Competence Res., Quantum Sci. Technol.Publisher: American Institute of Physics Inc.Allen, L., Eberly, J.H., (1975) Optical Resonance and Two Level Atoms, , New York :WileyLevine, B.F., (1993) J. Appl. Phys., 74 (8), pp. R1Müller, K., Reithmaier, G., Clark, E.C., Jovanov, V., Bichler, M., Krenner, H.J., Betz, M., Finley, J.J., (2011) Phys. Rev. B, 84, pp. 081302RAutler, S.H., Townes, C.H., Rev, P., (1955), 100, p. 703Madureira, J.R., Schulz, P.A., Maialle, M.Z., (2004) Phys. Rev. B, 70, p. 033309M. Z. Maialle, M. H. Degani, and J. R. Madureira, unpublishedSadeghi, S.M., Meyer, J., (1997) J. Phys.: Condens. Matter, 9, p. 768