Publications de Gordon Jens Callsen

Single photon emission and recombination dynamics in self-assembled GaN/AlN quantum dots

Nicolas Grandjean, Raphaël Butté, Sebastian Pascal Tamariz Kaufmann, Johann Nicolaï Stachurski, Gordon Jens Callsen

Y III-nitride quantum dots (QDs) are a promising system actively studied for their ability to maintain single photon emission up to room temperature. Here, we report on the evolution of the emission properties of self-assembled GaN/ AlN QDs for temperature ...

SPRINGERNATURE2022

Polariton relaxation and polariton nonlinearities in nonresonantly cw-pumped III-nitride slab waveguides

Jean-François Carlin, Nicolas Grandjean, Raphaël Butté, Joachim Armand Simonne Ciers, Gordon Jens Callsen

Polariton lasers are mostly based on planar cavities. Here we focus on an alternative configuration with slab waveguide modes strongly coupled to excitons confined in GaN/AlGaN quantum wells. We study experimentally and theoretically polariton relaxation a ...

2020

Toward Bright and Pure Single Photon Emitters at 300 K Based on GaN Quantum Dots on Silicon

Nicolas Grandjean, Raphaël Butté, Sebastian Pascal Tamariz Kaufmann, Johann Nicolaï Stachurski, Kanako Shojiki, Gordon Jens Callsen

Quantum dots (QDs) based on III-nitride semi-conductors are promising for single photon emission at noncryogenic temperatures due to their large exciton binding energies. Here, we demonstrate GaN QD single photon emitters operating at 300 K with g((2)) (0) ...

AMER CHEMICAL SOC2020

Probing Alloy Formation Using Different Excitonic Species: The Particular Case of InGaN

Nicolas Grandjean, Raphaël Butté, Gordon Jens Callsen

Since the early 1960s, alloys are commonly grouped into two classes that feature either bound states in the band gap (I) or additional, nondiscrete band states (II). Consequently, one can observe either excitons bound to isoelectronic impurities or the typ ...

American Physical Society2019

Probing alloy formation using different excitonic species: The particular case of InGaN

Nicolas Grandjean, Raphaël Butté, Gordon Jens Callsen

Since the 1960s, alloys are grouped into two classes, featuring bound states in the bandgap (I - GaP:N, ZnTe:O, etc.) or additional, non-discrete, band states (II - SiGe, GaAsP, InGaAs, etc.). Therefore, one can observe either a rich and informative zoo of ...

IEEE2019

Density control of GaN quantum dots on AlN single crystal

Nicolas Grandjean, Sebastian Pascal Tamariz Kaufmann, Gordon Jens Callsen

Full control over the density and emission properties of GaN quantum dots (QDs) should be feasible, provided that the growth proceeds in the Stranski-Krastanov (SK) growth mode. In this work, we derive the phase diagram for GaN QD formation on AlN by NH3-m ...

2019

Room temperature single photon emission from planar GaN/AlN quantum dot samples grown by MBE

Nicolas Grandjean, Sebastian Pascal Tamariz Kaufmann, Gordon Jens Callsen

We present an overview on the growth and the optical properties of GaN quantum dots (QDs) embedded in planar AlN grown on the following three different types of substrates: single AlN crystal, AlN on sapphire, and AIN on Si(111). QD density control over th ...

IEEE2019

A quantum optical study of thresholdless lasing features in high-beta nitride nanobeam cavities

Jean-François Carlin, Nicolas Grandjean, Raphaël Butté, Noelia Vico Triviño, Ian Michael Rousseau, Gordon Jens Callsen

Nature Research2018

Excited states of neutral donor bound excitons in GaN

Nicolas Grandjean, Raphaël Butté, Gordon Jens Callsen

2018

Optical absorption and oxygen passivation of surface states in III-nitride photonic devices

Jean-François Carlin, Nicolas Grandjean, Raphaël Butté, Gwénolé Jean Jacopin, Ian Michael Rousseau, Gordon Jens Callsen

2018

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

Suppression of the quantum-confined Stark effect in polar nitride heterostructuresis

Antoine Cyril David Hoffmann, Gordon Jens Callsen

Recently, we suggested an unconventional approach (the so-called Internal-Field-Guarded-Active-Region Design "IFGARD") for the elimination of the quantum-confined Stark effect in polar semiconductor heterostructures. The IFGARD-based suppression of the Sta ...

NATURE PUBLISHING GROUP2018