Quantum bits in carbon nanotubes

One step toward telecom-compatible quantum communication: new experimental results from the BME Spin Spectroscopy research group published in ACS Nano.

Quantum bits (qubits) emitting and absorbing photons in the telecom wavelength window (1300-1600 nm) are a key requirement for quantum communication based on fibre optics. However, the best-known, most popular solid-state qubits, such as the nitrogen-vacancy center in diamond, are active in the optical wavelength window (380-740 nm). Therefore, the recent experimental results of the BME Spin Spectroscopy research group, characterising the interaction of electrons in carbon nanotubes and telecom-wavelength photons, might be of high importance to establish novel telecom-compatible qubits. The authors believe that their findings may foster the application of carbon nanotubes in quantum technology. 

J. Palotás, M. Negyedi, S. Kollarics, A. Bojtor, P. Rohringer, T. Pichler, and F. Simon
Incidence of Quantum Confinement on Dark Triplet Excitons in Carbon Nanotubes
Web page of the research group:

YSR state in the news

New paper from the BME Nanoelectronics research group, published recently in Nature Communications, was covered in the news at, and the Hungarian news site Origo. Műegyetemi szakemberek újabb nemzetközi sikere a kvantumtudományban Lendületes kutatók mesterséges atomokra építenék a jövő kvantumszámítógépét

Origo: Magyar kutatók mesterséges atomokra építenék a jövő kvantumszámítógépét


Website of the Nanoelectronics group:


In their new paper, János Török and his colleagues provide support for the ancient idea of Plato that on Earth, "everything is built up from cubes". Also covered by


Gábor Domokos, Douglas J. Jerolmack, Ferenc Kun, and János Török
Plato’s cube and the natural geometry of fragmentation
Proceedings of the National Academy of Sciences of the United States of America (PNAS)
published on July 17, 2020


Report at (in Hungarian):

Electrically controlled spin current

Researchers of our Institute have created electrically controlled spin currents in a graphene-based nanostructure. Published in Nano Letters, in collaboration with Chalmers.


Zoltán Kovács-Krausz, Anamul Md Hoque, Péter Makk, Bálint Szentpéteri, Mátyás Kocsis, Bálint Fülöp, Michael Vasilievich Yakushev, Tatyana Vladimirovna Kuznetsova, Oleg Evgenevich Tereshchenko, Konstantin Aleksandrovich Kokh, István Endre Lukács, Takashi Taniguchi, Kenji Watanabe, Saroj Prasad Dash, and Szabolcs Csonka
Electrically Controlled Spin Injection from Giant Rashba Spin–Orbit Conductor BiTeBr
Nano Letters 20, 4782 (2020)
Home page of the BME Nanoelectronics research group:

Material for future devices

Material for future batteries and spintronic devices
Lithium shortage is an arising challenge due to the ever-increasing demand for lithium-ion based batteries. The problem could be solved by replacing lithium with sodium, which is a lot more abundant on Earth. However, until now, no one has managed to dope graphite -- which is the most common electrode in batteries -- with sodium in large enough concentrations. The researchers of the Spin-spectroscopy group of the Institute of Physics report the successful synthesis of highly sodium-doped graphene. The result was achieved in an international collaboration, and published by ACS Nano:
B. G. Márkus, P. Szirmai, K. F. Edelthalhammer, P. Eckerlein, A. Hirsch, F. Hauke, N. M. Nemes, Julio C. Chacón-Torres, B. Náfrádi, L. Forró, T. Pichler, and F. Simon
Ultralong Spin Lifetime in Light Alkali Atom Doped Graphene
The spin lifetime of electrons is also very long in this material, thus making it a good candidate for future spintronic devices. The publication was also highlighted by news site of the collaborating partner, the Swiss Federal Institute of Technology in Lausanne (EPFL). EPFL has a long-standing and fruitful collaboration with BME, and according to the latest QS World University Rankings, is the world's 14th best university.
Web page of the research group: