Publications de Naotomo Takemura

Polaritonic Cross Feshbach Resonance

Daniel Oberli, Marcia Portella Oberli, Naotomo Takemura, Mitchell David Anderson, Morteza Navadeh Toupchi

We demonstrate the existence of a cross Feshbach resonance by strongly driving a lower polariton mode and by monitoring in time the transmission of a short optical pulse at the energy of the upper polariton mode in a semiconductor microcavity. From the sig ...

2019

On the physics of polariton interactions

Naotomo Takemura

An exciton-polariton is a quasi-particle that emerges from the strong coupling between an exciton and a photon. Recently, the studies of the exciton-polariton have been receiving a great deal of attention in terms of both fundamental physics and potential ...

EPFL2016

Coherent and incoherent aspects of polariton dynamics in semiconductor microcavities

Benoît Marie Joseph Deveaud, Daniel Oberli, Marcia Portella Oberli, Naotomo Takemura, Mitchell David Anderson, Morteza Navadeh Toupchi, Souvik Biswas

The interaction between coherent polaritons and incoherent excitons plays an important role in polariton physics. Using resonant pump-probe spectroscopy with selective excitation of single polariton branches, we investigate the different dephasing mechanis ...

Amer Physical Soc2016

Two-dimensional Fourier transform spectroscopy of exciton-polaritons and their interactions

Benoît Marie Joseph Deveaud, Daniel Oberli, Marcia Portella Oberli, Verena Kohnle, Stéphane Trebaol, Naotomo Takemura, Mitchell David Anderson

We investigate polariton-polariton interactions in a semiconductor microcavity through two-dimensional Fourier transform (2DFT) spectroscopy. We observe, in addition to the lower-lower and the upper-upper polariton self-interactions, a lower-upper cross in ...

American Physical Society2015

Dephasing effects on coherent exciton-polaritons and the breakdown of the strong coupling regime

Benoît Marie Joseph Deveaud, Daniel Oberli, Marcia Portella Oberli, Stéphane Trebaol, Naotomo Takemura, Mitchell David Anderson, Souvik Biswas

Using femtosecond pump-probe spectroscopy, we identify excitation-induced dephasing as a major mechanism responsible for the breakdown of the strong coupling between excitons and photons in a semiconductor microcavity. The effects of dephasing are observed ...

American Physical Society2015

Heterodyne spectroscopy of polariton spinor interactions

Benoît Marie Joseph Deveaud, Marcia Portella Oberli, Stéphane Trebaol, Naotomo Takemura

We report on spinor polariton interactions in GaAs based microcavities. This investigation is carried out by means of heterodyne polarized pump-probe spectroscopy. We show the dependence of the energy renormalization of the lower and upper polariton resona ...

American Physical Society2014

Polaritonic Feshbach resonance

Benoît Marie Joseph Deveaud, Marcia Portella Oberli, Stéphane Trebaol, Naotomo Takemura

A Feshbach resonance occurs when the energy of two interacting free particles comes into resonance with a molecular bound state. When approaching this resonance, marked changes in the interaction strength between the particles can arise. Feshbach resonance ...

Nature Publishing Group2014