Technische Unversität Berlin

Technische Universitaet Berlin

Chinese Academy of Sciences

Changchun Institute of Optics, Fine Mechanics and Physics

Pbc Lasers Gmbh

Dieter Bimberg

Gunter Larisch

Andreas Marent

Matthias Strassburg

Andrei Schliwa

Udo W Pohl

Martin Geller

Oliver Schulz

Vladimir Kalosha

Vitaly Shchukin

Nikolai Ledentsov

Moritz Kleinert

Sicong Tian

Robert Seguin

James A Lott

Vladimir Gaysler

Momme Winkelnkemper

Sven Rodt

Anjin Liu

Werner Hofmann

Anatol Lochmann

Kristijan Posilovic

Ricardo Rosales

Tobias Nowozin

Roman Sellin

Erik Stock

Dejan Arsenijevic

Nikolai N Ledenstov

Nikolai N Ledentsov

A method of fabricating at least one radiation emitter including fabricating a layer stack that includes a first reflector, an active region, an oxidizable layer, and a second reflector; and locally removing the layer stack, and thereby forming at least one mesa. The mesa includes the first reflector, the active region, the oxidizable layer and the second reflector. Before or after locally removing the layer stack and forming the mesa the following steps are carried out: vertically etching at least three blind holes inside the layer stack, wherein the blind holes vertically extend to and expose the oxidizable layer; and oxidizing the oxidizable layer via the sidewalls of the blind holes in lateral direction. An oxidation front radially moves outwards from each hole. The etching is terminated before the entire oxidizable layer is oxidized, thereby forming at least one unoxidized aperture that is limited by at least three oxidation fronts.

Radiation emitter

An exemplary embodiment of the present invention relates to a method of fabricating at least one radiation emitter comprising the steps of depositing an etch stop layer on a top side of a substrate; depositing a layer stack on the etch stop layer, said layer stack comprising a first contact layer, a first reflector, an active region, a second reflector, and a second contact layer; locally removing the layer stack and the etch stop layer, and thereby forming at least one mesa, said at least one mesa comprising an unremoved section of the etch stop layer and a layered pillar which forms a vertical cavity laser structure based on the unremoved layer stack inside the at least one mesa; depositing a protection material on the top side of the substrate and thereby embedding the entire mesa in the protection material wherein the backside of the substrate remains unprotected; removing the substrate by applying at least one etching chemical that is capable of etching the substrate but incapable or less capable of etching the etch stop layer and the protection material; and removing the etch stop layer and thereby exposing the first contact layer of the at least one layered pillar.

Vertical-cavity surface-emitting laser

A method of fabricating a radiation emitter including fabricating a layer stack that includes a first reflector, at least one intermediate layer, an active region and a second reflector; locally oxidizing the intermediate layer and thereby forming at least one unoxidized aperture; and locally removing the layer stack, and thereby forming a mesa that includes the first reflector, the unoxidized aperture, the active region, and the second reflector. Before or after locally removing the layer stack and forming the mesa: forming at least a first unoxidized aperture and at least a second unoxidized aperture inside the intermediate layer; etching a trench inside the layer stack, the trench defining a first portion and a second portion of the mesa, wherein the trench severs the intermediate layer(s) so that the first aperture is located in the first portion and the second aperture is located in the second portion of the mesa.

A vertical cavity surface emitting laser comprising a first reflector, a second reflector comprising a layer stack of semiconductor or isolating layers, an active region arranged between the first and second reflectors, and an additional layer on top of the layer stack at the light output side, said additional layer forming an output interface of the laser, wherein the refractive index of the additional layer is smaller, equal to or larger than the smallest refractive index of the refractive indices of said layer stack.

An optoelectronic oscillator for generating an optical and/or electric pulse comb, comprising a monolithically integrated passively mode-coupled semiconductor laser and an optical feedback loop which guides a part of the optical radiation of the semiconductor laser and feeds said part back into the semiconductor laser as feedback pulses. Without the influence of the feedback pulses, the semiconductor laser would emit comb-like optical pulses, hereafter referred to as primary pulses, and in the event of an influence, emits comb-like output pulses which have been influenced by the feedback pulses, said output pulses having a lower temporal jitter or less phase noise than the primary pulses. The feedback loop is damped between 27.5 and 37.5 dB, and the time lag of the feedback loop is selected such that each feedback pulse is incident within the temporal half-value width of each subsequent primary pulse.

Optoelectronic oscillator

Device comprising a high brightness broad-area edge-emitting semiconductor laser and method of making the same. The device includes an edge-emitting semiconductor laser, said laser having a multi-layered waveguide, and said waveguide comprising at least one layer with an active region that emits light under electrical injection, and at least one aperiodic layer stack.

Device comprising a high brightness broad-area edge-emitting semiconductor laser and method of making the same

An optical sensor for detecting chemical, biochemical or biological substances includes a laser and a semiconductor chip. The sensor includes at least one photodetector and at least one high-contrast grating that are monolithically integrated in the semiconductor chip. The high-contrast grating is configured to optically couple radiation emitted by the laser into the photodetector. The coupling behavior of the high-contrast grating depends on the optical properties of external substances that are brought near to or in contact with the high-contrast grating.

Optical sensor for detecting chemical, biochemical or biological substances

An embodiment of the invention relates to a method for generating short optical pulses comprising the steps of:

Method and device for generating short optical pulses

The invention relates, inter alia, to a memory cell () comprising at least one binary memory area for storing bit information. According to the invention it is provided that the memory area (SB) can optionally store holes or electrons and allows a recombination of holes and electrons, the charge carrier type of the charge carriers stored in the memory area defines the bit information of the memory area, and a charge carrier injection device (PN) is present, by means of which optionally holes or electrons can be injected into the memory area (SB) and the bit information can thus be changed.

Memory cell

The invention relates to a method for the production of a photon pair source, which generates entangled photon pairs, having at least one quantum dot, wherein in the method the operational behaviour of the photon pair source is determined by adjusting the fine structure splitting of the excitonic energy level of the at least one quantum dot. It is provided according to the invention for the fine structure splitting of the excitonic energy level to be adjusted by depositing the at least one quantum dot on a {111} crystal surface of a semiconductor substrate.

Photon pair source and method for its production

In a method for the production of a single photon source with a given operational performance, the given operational performance for the individual photon source may be fixed by a directed setting of the fine structure gap of the excitonic energy level for at least one quantum dot. The at least one quantum dot is produced with a quantum dot size corresponding to the fine structure gap for setting.

Single-photon source and method for the production and operation thereof

An embodiment of the invention relates to a device comprising a laser and a waveguide stripe or netlike hexagonal stripe structure, which allows propagation of multitude of the lateral modes in the waveguide stripe or stripe structure, wherein the waveguide stripe has at least one corrugated edge section along its longitudinal axis to provide preferable amplification of the fundamental lateral mode or in-phase supermode and to obtain high brightness of the emitted radiation.

Device comprising a laser

An embodiment of the invention relates to a memory comprising a strained double-heterostructure having an inner semiconductor layer which is sandwiched between two outer semiconductor layers, wherein the lattice constant of the inner semiconductor layer differs from the lattice constants of the outer semiconductor layers, the resulting lattice strain in the double-heterostructure inducing the formation of at least one quantum dot inside the inner semiconductor layer, said at least one quantum dot being capable of storing charge carriers therein, and wherein, due to the lattice strain, the at least one quantum dot has an emission barrier of 1.15 eV or higher, and provides an energy state density of at least three energy states per 1000 nm, all said at least three energy states being located in an energy band of 50 meV or less.

Memory

An embodiment of the invention relates to a single-photon source for emitting single photons, comprising a cavity having a first mirror and a second mirror and exhibiting a longitudinal resonance frequency between the first and second mirror; at least one quantum dot arranged inside said cavity, said quantum dot being strain-dependent and configured to generate radiation at a strain-dependent radiation frequency; a device capable of exciting the quantum dot to generate radiation; a piezoelectric crystal being arranged outside the cavity and mechanically coupled to the second mirror's outer surface, said piezoelectric crystal configured to receive a control voltage and capable of applying either a laterally tensile and vertically compressive strain to both the cavity and the quantum dot, or a laterally compressive and vertically tensile strain to both the cavity and the quantum dot, depending on the control voltage's polarity; wherein, in response to said strain, the resonance frequency and the radiation frequency shift in opposite directions.

Single photon source

The invention relates, among other things, to a memory cell for storing at least one piece of bit data. Said memory cell comprises at least two electrical terminals and a semiconductor structure with a band curve (EL) that has at least one potential well. The charged state of the potential well with charge carries can be increased by applying a supply voltage (Us=Uspeis) to the two terminals, can be reduced by applying a discharge voltage (Us=Usperr), and can be maintained by applying a maintaining voltage (Us=Ubei), the respective charged state of the potential well defining the piece of bit data of the memory cell. According to the invention, the semiconductor structure has a space charge region (Wn) while the potential well is formed by a semiconductor heterostructure. The semiconductor heterostructure and the space charge region are spatially arranged relative to one another in such a way that the semiconductor heterostructure is located within the space charge region when the maintaining voltage is applied, at the edge of or outside the space charge region when the supply voltage is applied, and within the space charge region when the discharge voltage is applied.

Growing community of inventors

Berlin, Germany

Dieter Bimberg