Welcome to the Brandt group (E25)

Our research addresses new semiconductor materials and new spectroscopic methods for their characterization. For quantum information processing, we develop new tools based on magnetic resonance which allow to manipulate and detect the spin state of quantum bits via electrical transport measurements. As qubits, we in particular study the nuclear spins of ionized donors, which based on our pioneering work have been demonstrated to have coherence times of the order of an hour at room temperature, by far exceeding any other solid-state-based qubit system. We also investigate the electric readout of NV centers in diamond, either by Förster transfer or photoionization.

The magnetic resonance techniques developed also allow the sensitive analysis of defects in semiconductor devices such as solar cells e.g. made from amorphous silicon or organic semiconductors. On the materials’ side, we study the properties of nanocrystals, focusing on fundamental issues concerning their doping and the use of thin films composed of nanocrystals for photovoltaic and thermoelectric energy conversion. Furthermore, we investigate the ferromagnetism in Mn-doped semiconductors, exploring possibilities to manipulate their magnetic properties by incorporation of hydrogen or the application of mechanical stress. Finally, the effects of chemical treatments on semiconductor surfaces are studied in the context of photovoltaics, where a new method to suppress reflection losses in solar cells is developed, and with respect to biosensors, where the functionalization of Si and SiC is investigated.

Have a look at the pages describing this research in more detail. There, you will also find links to recent scientific publications. If you have more questions or would like to join us as a student or post doc, please contact Martin Brandt.

TUM Technische Universität München TUM Technische Universität München Physik Department Elektrotechnik und Informationstechnik TUM Technische Universität München

Recent publications

Interaction of Strain and Nuclear Spins in Silicon: Quadrupolar Effects on Ionized Donors

Phys. Rev. Lett. 115, 057601 (2015)

D. Franke | F. Hrubesch | M. Künzl | H. W. Becker | K. M. Itoh | M. Stutzmann | F. Hoehne | L. Dreher | M. S. Brandt

Online Reference

see also: Nuclear Spins of Ionized Phosphorus Donors in Silicon

Phys. Rev. Lett. 108, 027602 (2012)

L. Dreher | F. Hoehne | M. Stutzmann | M. S. Brandt

Online Reference

Ultrafast electronic read-out of diamond NV centers coupled to graphene

Nature Nanotechnology 10, 135 (2015)

A. Brenneis | L. Gaudreau | M. Seifert | H. Karl | M. S. Brandt | H. Huebl | J. A. Garrido | F. H. L. Koppens | A. Holleitner

Online Reference

Bipolar polaron pair recombination in polymer/fullerene solar cells

Physical Review B 92, 245203 (2015)

A. Kupijai | K. M. Behringer | F. Schäble | N. Galfe | M. Corazza | S. A. Gevorgyan | F. C. Krebs | M. Stutzmann | M. S. Brandt

Online Reference

Broadband electrically detected magnetic resonance using adiabatic pulses

Journal of Magnetic Resonance 254, 62 (2015)

F. Hrubesch | G. Braunbeck | A. Voss | M. Stutzmann | M. S. Brandt

Online Reference

High cooperativity coupling between a phosphorus donor spin ensemble and a superconducting microwave resonator

Appl. Phys. Lett. 107, 142105 (2015)

C. W. Zollitsch | K. Mueller | D. Franke | S. T. B. Goennenwein | M. S. Brandt | R. Gross | H. Huebl

Online Reference

Submillisecond Hyperpolarization of Nuclear Spins in Silicon

Phys. Rev. Lett. 114, 117602 (2015)

F. Hoehne | L. Dreher | D. Franke | M. Stutzmann | L. S. Vlasenko | K. M. Itoh | M. S. Brandt

Online Reference