Halbleiter-Nanostrukturen und -Quantensysteme

Prof. Jonathan Finley

Forschungsgebiet

Our group explores a wide range of topics related to the fundamental physics of nanostructured materials and their quantum-electronic and -photonic properties. We study the unique electronic, photonic and quantum properties of materials patterned over nanometer lengthscales and explore how sub-components can be integrated together to realise entirely new materials with emergent properties. This convergence of materials-nanotechnology, quantum electronics and photonics is strongly interdisciplinary, spanning topics across the physical sciences, as well as materials science and engineering.

Adresse/Kontakt

Am Coulombwall 4/I
85748 Garching b. München
+49 89 289 12771
Fax: +49 89 289 12704

Mitarbeiterinnen und Mitarbeiter der Arbeitsgruppe

Professorinnen und Professoren

Mitarbeiterinnen und Mitarbeiter

Lehrangebot der Arbeitsgruppe

Lehrveranstaltungen mit Beteiligung der Arbeitsgruppe

Ausgeschriebene Angebote für Abschlussarbeiten an der Arbeitsgruppe

Attaching wires to doped GaAs-AlGaAs core-multishell nanowire lasers

Semiconductor nanowires (NW) are rapidly emerging as a new generation of miniaturized on-chip coherent light sources by virtue of their unique geometry. In particular, due to the natural Fabry-Perot resonators formed by guided modes between the NW-endfacets, combined with the possibilities for direct monolithic integration on Si, NW lasers offer attractive applications in future optical interconnects and data communication.

Until now these NW lasers are driven optically, an electrical operation of the device is crucial for all applications. For this purpose, electrical contacts and a precise control of the doping profile in the device is required. The aim of this maswters thesis project is to develop appropriate process technologies to contact doped core-multishell NWs in a lying and standing geometry. This enables the characterization of the devices with respect to their electrical properties. Moreover, a comprehensive 2D-3D TCAD model of the NW laser will be implemented to simulate the electrothermal performance of the device. Adjusting the simulations to the measurement results enables the optimization of the doping profile and the heterostructure design of the NW laser. Experience in the area of clean room fabrication or TCAD modeling is a benefit, but secondary to motivation, commitment and a willingness to work as part of a team.

Applications should be sent to Prof. Finley (finley@wsi.tum.de)with c.c. to Jochen Bissinger (Jochen.Bissinger@wsi.tum.de). Please include a brief CV, a copy of your Bachelor Thesis and a transcript of your grades.

geeignet als
  • Masterarbeit Physik der kondensierten Materie
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Jonathan Finley
Imaging of Neural Action Potentials by Quantum Sensors and/or Deep Learning

Our young lab is using solid state qubits to build sensors, e.g. for magnetic fields. We aim to apply them to various applications, with a particular focus on life sciences.

Most of our projects focus on microscopy methods based on magnetic resonance spectroscopy of small (sub-µm) samples.

We are seeking a MSc student to study a novel application, imaging of electric action potentials of neurons, the cells performing computation in the brain. This should involve the development of a new type of sensor, based on solid state quantum materials, smart signal processing by artificial neural networks, or a combination of both.

Techniques:

* You will learn to prepare microscopy samples of both solid state samples and cell cultures. 

* You will design an experiment to detect the weak optical signals from these samples in one of our existing microscope setups. This will involve development of advanced optics and control software.  

Depending on preference and success of the initial steps you will either

* Study fluoresent quantum materials like red fluorescent diamond and their response to external electric fields. 

* Develop signal processing protocols to enhance these signals in existing devices 

 

geeignet als
  • Masterarbeit Physik der kondensierten Materie
  • Masterarbeit Kern-, Teilchen- und Astrophysik
  • Masterarbeit Biophysik
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Friedemann Reinhard
Nuclear Magnetic Resonance Microscopy

Magnetic resonance imaging (NMR/MRI), is one of the most powerful techniques to record three-dimensional images of nearly arbitrary samples. Current standard setups, such as those found in hospitals, cannot record details smaller than 1mm.  

Our group aims to push MRI to a microscopy technique by improving its spatial resolution down to the sub-nm range, the scale of single atoms. This ambitious goal has recently become a realistic prospect by a new generation of quantum sensors for magnetic fields. They are based on the nitrogen-vacancy (NV) color defect in diamond and could detect fields as small as the NMR signal of a single molecule [1,2].

We are looking for a MSc student to develop such a magnetic resonance microscope with a resolution in the intermediate (100nm-1µm) range, higher than any conventional technique, but coarser than most of our other (nm-range) projects. 

Techniques:

* You will learn to fabricate microscale electromagnets in one of our clean rooms, and optimize our fabrication techniques for your project and others. 

* You will design a sensor chip for microscale NMR detection and upgrade software and optics of one of our setups to perform the experiment. 

* You will design, implement and analyze quantum control protocols to record microscale MRI images.

[1] T. Staudacher et al., Science 339, 561 (2013)

[2] H.J. Mamin et al., Science 339, 557 (2013)

 
geeignet als
  • Masterarbeit Physik der kondensierten Materie
  • Masterarbeit Biophysik
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Friedemann Reinhard
Teaching Photons New Tricks: Mode control in monolithically integrated nanowire lasers
Reliable technologies for the monolithic integration of lasers onto silicon represent the holy grail for chip-level optical interconnects. In this context, nanowires (NW) fabricated using III−V semiconductors are of strong interest since they can be grown site-selectively on silicon using conventional epitaxial approaches. Their unique one-dimensional structure and high refractive index naturally facilitate low loss optical waveguiding and optical recirculation in the active NW region. In this versatile and ambitious project, a comprehensive 2D-3D TCAD model will be implemented to analyze a monolithically integrate NW laser on a silicon-on-insulator (SOI) substrate. The aim of this project is to design the cavity and the dielectric environment of the NW laser to control and manipulate its optical properties. Furthermore, the developed design approaches will be realized by different nanofabrication technologies and characterized by several optical measurements. Experience in the area of clean room fabrication or TCAD modeling is a benefit, but secondary to motivation and commitment. Applications should be sent to Prof. Finley (finley@wsi.tum.de) including Jochen Bissinger on c.c. (Jochen.Bissinger@wsi.tum.de). Please include your CV, a copy of your Bachelor Thesis and a transcript of your grades.
geeignet als
  • Masterarbeit Physik der kondensierten Materie
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Jonathan Finley

Abgeschlossene und laufende Abschlussarbeiten an der Arbeitsgruppe

Continuous Wave Lasing and First-Order Coherence of Semiconductor Nanowire Lasers
Abschlussarbeit im Masterstudiengang Physik (Physik der kondensierten Materie)
Themensteller(in): Jonathan Finley
Low Power Hybrid Plasmonic Modulator For On-Chip Optical Interconnects
Abschlussarbeit im Masterstudiengang Physics (Applied and Engineering Physics)
Themensteller(in): Jonathan Finley
Correlated He-Ion microscopy and atomic force microscopy of III-V semiconductor heterostructures
Abschlussarbeit im Bachelorstudiengang Physik
Themensteller(in): Jonathan Finley
Sensing Weak High Frequency Signals by Quantum Control
Abschlussarbeit im Masterstudiengang Physics (Applied and Engineering Physics)
Themensteller(in): Friedemann Reinhard
Optical Characterization of GaAs-based Nanowire Lasers Integrated on Silicon Waveguides
Abschlussarbeit im Masterstudiengang Physik (Physik der kondensierten Materie)
Themensteller(in): Jonathan Finley
Optical and Electrical Properties of Quantum Confined GaAs-AlGaAs Core-Shell Nanowire
Abschlussarbeit im Masterstudiengang Physik (Physik der kondensierten Materie)
Themensteller(in): Jonathan Finley
Optical, Vibrational and Valleytronic Properties of Helium Ion Modified Atomically Thin MoS₂
Abschlussarbeit im Masterstudiengang Physik (Physik der kondensierten Materie)
Themensteller(in): Jonathan Finley
Quantum Dot Single Photon Sources and their Applications in Quantum Photonic Integrated Circuits
Abschlussarbeit im Masterstudiengang Physics (Applied and Engineering Physics)
Themensteller(in): Jonathan Finley
Simulation und optische Oharakterisierung
Abschlussarbeit im Bachelorstudiengang Physik
Themensteller(in): Jonathan Finley
Transient Rayleigh Scattering of single SixGe1-x Nanowires
Abschlussarbeit im Masterstudiengang Physik (Physik der kondensierten Materie)
Themensteller(in): Jonathan Finley

Kondensierte Materie

Wenn Atome sich zusammen tun, wird es interessant: Grundlagenforschung an Festkörperelementen, Nanostrukturen und neuen Materialien mit überraschenden Eigenschaften treffen auf innovative Anwendungen.