Publications de Georg Rossbach

Impact of alloy disorder on Auger recombination in single InGaN/GaN core-shell microrods

Benoît Marie Joseph Deveaud, Christian Mounir, Georg Rossbach, Gwénolé Jean Jacopin, Wei Liu

We study the influence of local inhomogeneities on carrier recombination dynamics in single InGaN/GaN core-shell microrods (MRs) by means of time-resolved microphotoluminescence (TRPL) at 10 K. At low carrier density (similar to 10(11) cm(-2)), the carrier ...

2019

Optical absorption edge broadening in thick InGaN layers: Random alloy atomic disorder and growth mode induced fluctuations

Jean-François Carlin, Nicolas Grandjean, Raphaël Butté, Marlene Glauser, Georg Rossbach, Lise Lahourcade, Gordon Jens Callsen

AIP American Institute of Physics2018

Spatially dependent carrier dynamics in single InGaN/GaN core-shell microrod by time-resolved cathodoluminescence

Benoît Marie Joseph Deveaud, Georg Rossbach, Gwénolé Jean Jacopin, Wei Liu

AIP American Institute of Physics2018

Enhancement of Auger recombination induced by carrier localization in InGaN/GaN quantum wells

Benoît Marie Joseph Deveaud, Nicolas Grandjean, Raphaël Butté, Mehran Shahmohammadi, Georg Rossbach, Lise Lahourcade, Gwénolé Jean Jacopin, Wei Liu

The origin of efficiency droop in state-of-the-art quality In GaN/GaN and GaN/AlGaN quantum wells (QWs) grown on various crystal planes is studied by means of time-resolved photoluminescence spectroscopy associated with a precise determination of the QW ca ...

Amer Physical Soc2017

Biexcitonic molecules survive excitons at the Mott transition

Jean-François Carlin, Benoît Marie Joseph Deveaud, Jean-Daniel Ganière, Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Mehran Shahmohammadi, Georg Rossbach, Gwénolé Jean Jacopin

When the carrier density is increased in a semiconductor, according to the predictions of Sir Nevil Mott, a transition should occur from an insulating state consisting of a gas of excitons to a conductive electron-hole plasma. This crossover, usually refer ...

Nature Publishing Group2014

M-Plane GaN/InAlN Multiple Quantum Wells in Core-Shell Wire Structure for UV Emission

Jean-François Carlin, Nicolas Grandjean, Raphaël Butté, Georg Rossbach

We report on the epitaxial growth of high-quality core-shell nonpolar m-plane GaN/InAlN multiple quantum wells (MQWs) on the sidewall facets of c-oriented hexagonal GaN wires. Pseudomorphic growth without generation of threading dislocations has been estab ...

Amer Chemical Soc2014

High-Density Excitonic Effects in GaN : Mott-Transition and Polariton Lasing

Georg Rossbach

EPFL2014

InGaN/GaN quantum wells for polariton laser diodes: Role of inhomogeneous broadening

Jean-François Carlin, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Marlene Glauser, Christian Mounir, Georg Rossbach

Contrary to the case of III-nitride based visible light-emitting diodes for which the inhomogeneous linewidth broadening characteristic of InGaN-based multiple quantum well (MQW) heterostructures does not appear as a detrimental parameter, such a broadenin ...

Amer Inst Physics2014

Q-factor of (In,Ga)N containing III-nitride microcavity grown by multiple deposition techniques

Jean-François Carlin, Gatien Cosendey, Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Marlene Glauser, Georg Rossbach

A 3 lambda/2 (In,Ga)N/GaN resonant cavity, designed for similar to 415nm operation, is grown by molecular beam epitaxy and is sandwiched between a 39.5-period (In,Al)N/GaN distributed Bragg reflector (DBR), grown on c-plane GaN-on-sapphire pseudo-substrate ...

Amer Inst Physics2013

Impact of saturation on the polariton renormalization in III-nitride based planar microcavities

Jean-François Carlin, Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Georg Rossbach

It has been widely observed that an increasing carrier density in a strongly coupled semiconductor microcavity (MC) alters the dispersion of cavity polaritons, below and above the condensation threshold. The interacting nature of cavity polaritons stems fr ...

Amer Physical Soc2013

Blue monolithic AlInN-based vertical cavity surface emitting laser diode on free-standing GaN substrate

Jean-François Carlin, Gatien Cosendey, Nicolas Grandjean, Antonino Francesco Castiglia, Georg Rossbach

We report on III-nitride based blue vertical cavity surface emitting lasers using defect-free highly reflective AlInN/GaN distributed Bragg reflectors grown on c-plane free-standing GaN substrates. Lasing is demonstrated at room temperature under pulsed el ...

American Institute of Physics2012

Generic picture of the emission properties of III-nitride polariton laser diodes: Steady state and current modulation response

Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Marlene Glauser, Georg Rossbach, Munise Nevin Cobet

The main emission characteristics of electrically driven polariton lasers based on planar GaN microcavities with embedded InGaN quantum wells are studied theoretically. The polariton emission dependence on pump current density is first modeled using a set ...

Amer Physical Soc2012

Nonlinear emission properties of an optically anisotropic GaN-based microcavity

Gatien Cosendey, Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Marlene Glauser, Georg Rossbach, Munise Nevin Cobet

The pronounced optical in-plane anisotropy of a suitably designed nonpolar GaN-based microcavity, mainly inherited from the valence-band complexity of wurtzite semiconductors, allows the coexistence of two different light-matter coupling regimes along orth ...

Amer Physical Soc2012

Impact of biexcitons on the relaxation mechanisms of polaritons in III-nitride based multiple quantum well microcavities

Jean-François Carlin, Benoît Marie Joseph Deveaud, Jean-Daniel Ganière, Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Gabriel Christmann, Pierre Michel Corfdir, Georg Rossbach

We report on the direct observation of biexcitons in a III-nitride based multiple quantum well microcavity operating in the strong light-matter coupling regime by means of nonresonant continuous wave and time-resolved photoluminescence at low temperature. ...

2012

High quality factor two dimensional GaN photonic crystal cavity membranes grown on silicon substrate

Jean-François Carlin, Romuald Houdré, Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Kirill Atlasov, Antonino Francesco Castiglia, Ulagalandha Perumal Dharanipathy, Noelia Vico Triviño, Georg Rossbach

We report on the achievement of freestanding GaN photonic crystal L7 nanocavities with embedded InGaN/GaN quantum wells grown by metal organic vapor phase epitaxy on Si (111). GaN was patterned by e-beam lithography, using a SiO2 layer as a hard mask, and ...

American Institute of Physics2012

Polariton lasing in a hybrid bulk ZnO microcavity

Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Georg Rossbach

We demonstrate polariton lasing in a bulk ZnO planar microcavity under non-resonant optical pumping at a small negative detuning (delta similar to -1/6 the 130 meV vacuum Rabi splitting) and a temperature of 120 K. The strong coupling regime is maintained ...

AIP American Institute of Physics2011

Tailoring the light-matter coupling in anisotropic microcavities: Redistribution of oscillator strength in strained m-plane GaN/AlGaN quantum wells

Gatien Cosendey, Jacques Levrat, Nicolas Grandjean, Raphaël Butté, Marlene Glauser, Georg Rossbach, Munise Nevin Cobet

We present a comprehensive study of the anisotropic optical properties of nonpolar GaN/AlGaN multiple quantum wells intentionally designed to act as an active region of a planar microcavity operating in the strong-coupling regime. The strain induced by the ...

2011