相关论文: Ultrafast cascade charge transfer in multi bandgap…
Materials with optical gain in the infrared are of paramount importance for optical communications, medical diagnostics and silicon photonics. The current technology is based either on costly III-V semiconductors that are not monolithic to…
Materials with optical gain in the infrared are of paramount importance for optical communications, medical diagnostics1 and silicon photonics2,3 . The current technology is based either on costly III-V semiconductors that are not…
Pb-chalcogenide colloidal quantum dots (CQDs) are attractive materials to be used as tuneable laser media across the infrared spectrum. However, excessive nonradiative Auger recombination due to the presence of trap states outcompetes light…
Steady-state access to intraband transitions in colloidal quantum dots (CQDs), via heavy doping, allows exploiting the electromagnetic spectrum at energies below the band gap. CQD intraband optoelectronics opens up a new path to cheap mid-…
The use of colloidal quantum dots (CQDs) as a gain medium in infrared laser devices has been underpinned by the need for high pumping intensities, very short gain lifetimes and low gain coefficients.
Quantum cascade detectors (QCD) are unipolar infrared devices where the transport of the photo excited carriers takes place through confined electronic states, without an applied bias. In this photovoltaic mode, the detector's noise is not…
Quantum dot - graphene hybrid materials have raised significant interest due to the unique synergy of the optical properties of colloidal quantum dots (QDs) and the transport properties of graphene. This stimulated the development of…
Unbalanced charge injection is deleterious for the performance of colloidal quantum dot (CQD) light emitting diodes (LEDs) as it deteriorates the quantum efficiency (QE), brightness and operational lifetime. CQD LEDs emitting in the…
Hybrid circuit quantum electrodynamics (cQED) aims at coupling various quantum degrees of freedom, among which are spin and charge degrees of freedom in gate defined quantum dots, phonons or magnons... with quantized electromagnetic fields…
Colloidal nanocrystals are unique optical gain materials due to their high intrinsic absorption, excellent quantum yield, and tunable emission. However, integration of colloidal nanocrystal solutions into photonic systems for lasing…
We employ time-resolved optical reflectivity to investigate the ultrafast dynamics of the charge-transfer gap (CTG) in a parent cuprate compound Ca$_2$CuO$_2$Cl$_2$ (CCOC). We observe a persistent photoinduced red shift of the CTG that…
Cavity quantum electrodynamics (cQED) provides strong light-matter interactions that can be used for manipulating and detecting quantum states. The interaction can be enhanced by increasing the resonator's impedance, while approaching the…
Hybrid quantum dot (QD) / transition metal dichalcogenide (TMD) heterostructures are attractive components of next generation optoelectronic devices, which take advantage of the spectral tunability of QDs and the charge and exciton…
We show that mid infrared transmission spectroscopy of a quantum cascade laser provides clear cut information on changes in charge location at different bias. Theoretical simulations of the evolution of the gain/absorption spectrum for the…
The interaction of exciton and charge transfer (CT) states plays a central role in photo-induced CT processes in chemistry, biology and physics. In this work, we use a combination of two-dimensional electronic spectroscopy (2D-ES),…
We present a theoretical analysis of intraband optical transitions from the intermediate pseudo-band of confined states to the conduction band in a finite, inhomogeneous stack of self-assembled semiconductor quantum dots. The chain is…
We present evidence of cavity quantum electrodynamics from a sparse density of strongly quantum-confined Pb-chalcogenide nanocrystals (between 1 and 10) approaching single-dot levels on moderately high-Q mesoscopic silicon optical cavities.…
The strong-coupling regime of cavity-quantum-electrodynamics (cQED) represents light-matter interaction at the fully quantum level. Adding a single photon shifts the resonance frequencies, a profound nonlinearity. cQED is a test-bed of…
Unique optical properties of colloidal semiconductor quantum dots (QDs), arising from quantum mechanical confinement of charge within these structures, present a versatile testbed for the study of how high electric fields affect the…
Realizing solution processed quantum dot (QD) lasers is one of the holy-grails of nanoscience. The reason that QD lasers are not yet commercialized is that the lasing threshold is too high: one needs > 1 exciton per QD, which is hard to…