The newest study was published in Journal of Applied Physics by Rusnė Ivaškevičiūtė-Povilauskienė et al. about the advantages of optical modulation in terahertz imaging for study of graphene layers.
It was demonstrated that optical modulation together with simultaneous terahertz (THz) imaging application enables an increase in contrast by an order of magnitude, thereby illustrating the technique as a convenient contactless tool for characterization of graphene deposited on high-resistivity silicon substrates.
The technique is applied in the development and investigation of graphene-based optical diffractive elements for THz imaging systems.
The work achieved funding from Horizon 2020 program under Grant No. 823728 (DiSetCom) as well as by the Academy of Finland Flagship Programme “Photonics Research and Innovation (PREIN)” (Decision No. 320165).
Rolando Maskoliūno vedamoje laidoje ”Smalsumo genas” (transliuojama per LRT) kalbama apie metamedžiagas ir terahercų technologiją. Apie vykdomus metamedžiagų tyrimus FTMC pasakoja Dr. Dalius Seliuta, o apie terahercų taikymus — Dr. Linas Minkevičius.
Traditional THz Atelier Table Football Championship was held just before Christmas. Ten participants registered to this event to prove themself as skillful players.
Five teams were competing for the very nice looking newly established prize. The prize is introduced this year and now will pass every year to new champions.
The teams were created randomly from the list of registered players using sophisticated algorithm just before the start of the championship. It was done to avoid illegal preliminary agreements among players despite some fierce protests.
After set of games the winners were announced and the prize was awarded to Dr. Mindaugas Karaliūnas and Vladislovas Čižas team. Congratulations to the new champions!
By the way, due to COVID-19 pandemic last year table football championship was postponed until this year. Looking forward to meet at the same table next year.
New principle and at the same time a new type of compact high-frequency radiation source operating at room temperature that can be placed on a semiconductor chip is suggested. It is broadband and can operate in the both GHz and THz frequency bands. Operation of the device relies on principles of the quantum optoelectronics (Esaki-Tsu nonlinearity of the quantum super-lattice), and employ drift-relaxation modes to amplify high-frequency radiation, which propagates in a semiconductor superlattice along its axis at a speed approximately 1000 times slower than the speed of light in a material. It can be realized in semiconductor superlattice with non-ohmic injection contacts of an appropriate design.
Patent No. LT2021567. At the time of writing this post some public access restrictions were implemented on this patent.
We work for the TERAOPTICS project at the Terahertz Photonics Laboratory (FTMC). Warm welcome to Krishna Kumar from the DAS Photonics and Polytechnic University of Valencia (Spain) being with us for next two weeks.
Recent work published in AIP Advanced journal by Agnieszka Siemion et. al reports on advances in Terahertz digital holography implementing two- and four-step phase shifting technique. Proposed holographic technique shows many advantages in THz imaging such as better contrast, reconstruction of 3D image and etc.
New paper by M. Karaliūnas et al. “High precision parabolic quantum wells grown using pulsed analog alloy grading technique: Photoluminescence probing and fractional-dimensional space approach” reports the findings on PL characterization with the help of fractional-dimensional space approach revealed precisely grown parabolic quantum well using molecular beam epitaxy pulsed analog alloy grading technique. The study presents beautiful physics of electrons being confined in 52-nm-width parabolic quantum well and proves the validity of Khon theorem. The work was supported by European Social Fund (project No 09.3.3-LMT-K-712-02-0172) under grant agreement with the Research Council of Lithuania (LMTLT). It can be reached via DOI: 10.1016/j.jlumin.2021.118321
Impressive review by G. Valušis et al. is published in Sensors (MDPI) journal. The roadmap article is focused on the most recent advances in THz imaging with particular attention paid to the optimization and miniaturization of the THz imaging system. Although the research on preparing the review haven’t received dedicated funding, the work covers the results of number of grants: Deutsche Forschungsgemeinschaft, contracts RO 770/40, /43 and /48, ME5034/2; Messer Stiftung, project “Orts- und zeitaufgelöste Spektroskopie an plasmonischen Strukturen mittels s-SNOM-Nanoskopie”, IRAP Programme of the Foundation for Polish Science (grant MAB/2018/9, project CENTERA), project KITKAS, founded by Lithuanian Research Council, LAT-04/2016. The work is accessible via DOI: 10.3390/s21124092