Article
Materials Science, Multidisciplinary
F. Godejohann, R. R. Akhmadullin, K. V. Kavokin, D. R. Yakovlev, I. A. Akimov, B. R. Namozov, Yu. G. Kusrayev, G. Karczewski, T. Wojtowicz, M. Bayer
Summary: A trion magnetic polaron formed by the exchange interaction of a positively charged exciton (trion) with localized spins of Mn2+ ions is experimentally observed. The trion is created from a resident hole in a hole magnetic polaron state and a photogenerated electron-hole pair. The dynamical evolution from the hole magnetic polaron to the trion magnetic polaron is accompanied by a spin flip of the electron, resulting in negative circular polarization of the photoluminescence. The spin polarization is maintained by the different localization sizes of the resident and photogenerated holes and their exchange interactions with the Mn2+ spins.
Article
Nanoscience & Nanotechnology
Florian N. M. Froning, Leon C. Camenzind, Orson A. H. van der Molen, Ang Li, Erik P. A. M. Bakkers, Dominik M. Zumbuehl, Floris R. Braakman
Summary: Quantum computers promise to execute complex tasks exponentially faster than classical computers, but require fast and selective control of individual qubits while maintaining coherence. Operating a hole spin qubit in a Ge/Si nanowire all-electrically demonstrates the principle of switching between fast control and increased coherence.
NATURE NANOTECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
I. R. de Assis, R. Raimondi, G. J. Ferreira
Summary: Controlling the spin dynamics and spin lifetimes is a major challenge in spintronics. Research has shown that a persistent spin helix regime with a long lifetime can be achieved when the Rashba and Dresselhaus spin-orbit couplings are balanced. The intersubband scattering rate, controlled by electric fields and maximized for symmetric quantum wells, is a key factor in controlling spin dynamics and can lead to reduced diffusion constants and longer spin lifetimes.
Article
Chemistry, Multidisciplinary
Ina Kalitukha, Olga S. Ken, Vladimir L. Korenev, Ilya A. Akimov, Victor F. Sapega, Dmitri R. Yakovlev, Grigorii S. Dimitriev, Lukas Langer, Grzegorz Karczewski, Sergij Chusnutdinow, Tomasz Wojtowicz, Manfred Bayer
Summary: In a Fe/(Cd,Mg)Te/CdTe quantum well hybrid structure, short-range and long-range ferromagnetic proximity effects are found to coexist for conduction band electrons and holes bound to shallow acceptors, respectively. These effects arise from different physical mechanisms and result from the interaction of charge carriers in the quantum well with different ferromagnetic materials.
Article
Chemistry, Multidisciplinary
Wiktoria Solarska, Krzysztof Karpierz, Maciej Zaremba, Florian Le Mardele, Ivan Mohelsky, Adam Siemaszko, Mikolaj Grymuza, Lucja Kipczak, Natalia Zawadzka, Maciej R. Molas, Eryk Imos, Zbigniew Adamus, Tomasz Slupinski, Tomasz Wojtowicz, Milan Orlita, Adam Babinski, Jerzy Lusakowski
Summary: Modulation-doped CdTe quantum wells with Cd0.7Mg0.3Te barriers were studied using PL, far-infrared Fourier spectroscopy, and Raman spectroscopy. The research compared two samples with different numbers of QWs and observed differences in PL characteristics. The analysis suggested that these differences were caused by variations in the recombination of electrons and holes in the conduction band.
Article
Materials Science, Multidisciplinary
L. V. Kotova, A. V. Platonov, R. Andre, H. Mariette, V. P. Kochereshko
Summary: In this study, photoluminescence and polarized reflection spectra were investigated in quantum well structures with symmetric and asymmetric barriers. The phenomenon of light birefringence was observed in structures with asymmetric barriers, which was attributed to the lower symmetry of the interfaces compared to the bulk crystals. The discussion about this phenomenon is presented.
Article
Chemistry, Multidisciplinary
Luana C. de Camargo, Matteo Briganti, Francielli S. Santana, Danilo Stinghen, Ronny R. Ribeiro, Giovana G. Nunes, Jaisa F. Soares, Enrico Salvadori, Mario Chiesa, Stefano Benci, Renato Torre, Lorenzo Sorace, Federico Totti, Roberta Sessoli
Summary: The study demonstrates that the 17-electron mixed sandwich complex has a remarkable coherence time at low temperatures, making it ideal for surface single-qubit addressing and quantum sensing applications.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Kunio Shimura, TaeGi Lee, Tatsuya Ito, DaeGwi Kim
Summary: The formation of CdS shell can be controlled by varying the Te/Cd ratio of the precursor solution during the synthesis of CdTe and CdTe/CdS QDs, allowing for the selective synthesis of QDs with the same PL energy but different PL decay times.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2021)
Article
Multidisciplinary Sciences
Go Yumoto, Hideki Hirori, Fumiya Sekiguchi, Ryota Sato, Masaki Saruyama, Toshiharu Teranishi, Yoshihiko Kanemitsu
Summary: By utilizing the multiband structure induced by strong spin-orbit coupling in lead halide perovskites, researchers have demonstrated an anomalous enhancement of exciton energy shift at room temperature. This enhancement at room temperature allows for efficient coherent optical manipulation of excitons utilizing energy states with large spin-orbit splitting, potentially opening up new possibilities for quantum state engineering and ultrafast optical modulation.
NATURE COMMUNICATIONS
(2021)
Article
Crystallography
Rafal Jakiela, Andrzej Mycielski, Dominika M. Kochanowska, Aneta Wardak, Barbara Witkowska, Michal Kochanski, Marta Witkowska-Baran, Gabriela Janusz, Marcin Dopierala, Adam Marciniak
Summary: The aim of the study was to establish the relationship between the measured concentration of vanadium in doped crystals and the vanadium concentration introduced during the growth process. Measurements using Secondary Ion Mass Spectrometry (SIMS) showed that for concentrations ranging from 10(14) cm(-3) to 3 x 10(18) cm(-3), the measured results differed from the intended values by not more than a factor of 2 and exhibited a linear relationship. However, for concentrations above 3 x 10(18) cm(-3), the measured vanadium concentrations were lower than the nominal ones by more than a factor of 10.
JOURNAL OF CRYSTAL GROWTH
(2021)
Article
Physics, Multidisciplinary
A. Hijano, E. J. Rodriguez, D. Bercioux, D. Frustaglia
Summary: This work investigates the response of spin carriers to effective field textures in curved one-dimensional interferometric circuits, finding that the interplay between Rashba and Dresselhaus spin-orbit interactions and circuit geometry modifies the geometric characteristics of spinors, resulting in the localization of electronic wave function and suppression of quantum conductance.
COMMUNICATIONS PHYSICS
(2023)
Article
Multidisciplinary Sciences
G. J. Ferreira, D. R. Candido, F. G. G. Hernandez, G. M. Gusev, E. B. Olshanetsky, N. N. Mikhailov, S. A. Dvoretsky
Summary: This article investigates the characteristics of triple HgTe quantum wells through theoretical and experimental research, and presents findings on topological phases, phase transitions, and transport measurements.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Applied
L. Bellentani, M. Bina, S. Bonen, A. Secchi, A. Bertoni, S. P. Voinigescu, A. Padovani, L. Larcher, F. Troiani
Summary: Hole spins in semiconductor quantum dots provide a potential route for electrically controlled qubits, with Si p-MOSFETs showing great potential for integration and scalability. Simulations of a hole-spin qubit in a downscaled Si-channel p-MOSFET demonstrate the formation of well-defined hole quantum dots and the possibility of electrical control.
PHYSICAL REVIEW APPLIED
(2021)
Article
Materials Science, Multidisciplinary
Josephine Dias, Christopher W. Waechtler, Victor M. Bastidas, Kae Nemoto, William J. Munro
Summary: The transfer of energy through a network of nodes is crucial to nature and technology. By replacing traditional channels with collective environments, energy can be efficiently transferred from one node to another even at zero temperature, showing potential for future quantum technologies.
Article
Physics, Applied
Jelmer M. Boter, Juan P. Dehollain, Jeroen P. G. van Dijk, Yuanxing Xu, Toivo Hensgens, Richard Versluis, Henricus W. L. Naus, James S. Clarke, Menno Veldhorst, Fabio Sebastiano, Lieven M. K. Vandersypen
Summary: This article discusses a quantum-dot spin-qubit architecture that integrates on-chip control electronics, reducing the number of signal connections at the chip boundary. It presents a concrete floor plan and estimates the operation frequencies and power consumption of a million-qubit array. This work significantly closes the gap towards a fully CMOS-compatible quantum computer implementation.
PHYSICAL REVIEW APPLIED
(2022)
Article
Chemistry, Physical
Bartlomiej Turowski, Aleksandr Kazakov, Rafal Rudniewski, Tomasz Sobol, Ewa Partyka-Jankowska, Tomasz Wojciechowski, Marta Aleszkiewicz, Wojciech Zaleszczyk, Magdalena Szczepanik, Tomasz Wojtowicz, Valentine V. Volobuev
Summary: In this study, the spin-polarization and electronic structure of (111)-oriented Pb1-xSnxSe topological crystalline insulator epitaxial films were investigated using angle-resolved photoemission spectroscopy and spin-resolved photoemission spectroscopy. It was found that the surface states can exhibit a gap opening by changing the Sn content or depositing a transition metal on the surface of the epitaxial layer. The observed helical spin polarization exists not only in topological samples but also in trivial samples. This work paves the way for the application of surface states in spin-charge conversion devices based on lead-tin chalcogenides.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Roman A. Babunts, Yulia A. Uspenskaya, Nikolai G. Romanov, Sergei B. Orlinskii, Georgy V. Mamin, Elena V. Shornikova, Dmitri R. Yakovlev, Manfred Bayer, Furkan Isik, Sushant Shendre, Savas Delikanli, Hilmi Volkan Demir, Pavel G. Baranov
Summary: Semiconductor colloidal nanoplatelets based on CdSe with magnetic Mn2+ ions show modified magneto-optical and spin-dependent properties. High-frequency electron paramagnetic resonance techniques were used to study the spin structure and dynamics of Mn2+ ions in core/shell CdSe/(Cd,Mn)S nanoplatelets. Two sets of resonances were observed, indicating different spin dynamics between surface and inner Mn2+ ions. The interaction between surface Mn2+ ions and 1H nuclei was measured using electron nuclear double resonance, providing information on the distances between Mn2+ ions and 1H nuclei.
Article
Chemistry, Multidisciplinary
Koloman Wagner, Zakhar A. Iakovlev, Jonas D. Ziegler, Marzia Cuccu, Takashi Taniguchi, Kenji Watanabe, Mikhail M. Glazov, Alexey Chernikov
Summary: This study demonstrates the diffusion of excitons in a monolayer semiconductor with a continuously tunable Fermi sea of free charge carriers. The light emission from tightly bound exciton states in electrically gated WSe2 monolayer is detected using microscopy. The measurements reveal a nonmonotonic dependence of the exciton diffusion coefficient on the charge carrier density.
Article
Chemistry, Multidisciplinary
Carolin Harkort, Dennis Kudlacik, Natalia E. E. Kopteva, Dmitri R. R. Yakovlev, Marek Karzel, Erik Kirstein, Oleh Hordiichuk, Maksym V. V. Kovalenko, Manfred Bayer
Summary: This article discusses the optical properties and spin phenomena of Ruddlesden-Popper type (PEA)(2)PbI4 perovskites. The Zeeman splitting of electrons and holes in a magnetic field was measured using spin-flip Raman scattering. The electron and hole g factors were evaluated, their anisotropies were measured, and the dynamic nuclear spin polarization induced by spin-polarized holes was detected.
Article
Multidisciplinary Sciences
E. Kirstein, N. E. Kopteva, D. R. Yakovlev, E. A. Zhukov, E. V. Kolobkova, M. S. Kuznetsova, V. V. Belykh, I. A. Yugova, M. M. Glazov, M. Bayer, A. Greilich
Summary: The spin dynamics and interaction of confined electrons or holes in perovskite nanocrystals are investigated using time resolved optical spectroscopy. Spin mode locking effect and nuclear focusing are observed in CsPb(Cl0.56Br0.44)(3) lead halide perovskite nanocrystals embedded in a glass matrix. The measured spin coherence time and spin dephasing time are 13 ns and a nanosecond respectively, and the developed theoretical model agrees well with the experimental data.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Stefan Grisard, Artur V. V. Trifonov, Ivan A. A. Solovev, Dmitri R. R. Yakovlev, Oleh Hordiichuk, Maksym V. V. Kovalenko, Manfred Bayer, Ilya A. A. Akimov
Summary: The compositional engineering of hybrid organic-inorganic lead halide perovskites is crucial for efficient solar cells and light-emitting devices. A study on the effect of bandgap fluctuations on coherent exciton dynamics in a mixed FA(0.9)Cs(0.1)PbI(2.8)Br(0.2) perovskite crystal using photon echo spectroscopy reveals a narrow homogeneous exciton line width and an exceptionally long exciton coherence time due to exciton localization at the nanoscale. The spectral and temperature dependences of the photon echo decay indicate that pure decoherence associated with elastic scattering on phonons is comparable with the exciton lifetime for low-energy excitons, while inelastic scattering to lower energy states dominates for high-energy excitons through phonon emission.
Article
Chemistry, Multidisciplinary
Changxiu Li, Alexey V. V. Scherbakov, Pedro Soubelet, Anton K. K. Samusev, Claudia Ruppert, Nilanthy Balakrishnan, Vitalyi E. E. Gusev, Andreas V. V. Stier, Jonathan J. J. Finley, Manfred Bayer, Andrey V. V. Akimov
Summary: The development of new techniques for ultrafast control of physical properties in 2D van der Waals nanolayers is necessary due to the increasing role of 2D devices. Heterobilayers assembled from van der Waals monolayers have the special feature of femtosecond separation of photoexcited electrons and holes between neighboring layers, resulting in the formation of Coulomb force. Coherent phonons generated in MoSe2/WSe2 heterobilayers through laser pulses can modulate the thickness of the heterobilayer and the photogenerated electric field in the van der Waals gap. Additionally, the modulation of the van der Waals gap by coherent phonons enables the generation of THz radiation in 2D nanodevices with van der Waals heterobilayers.
Editorial Material
Nanoscience & Nanotechnology
Mikhail M. Glazov
NATURE NANOTECHNOLOGY
(2023)
Article
Physics, Applied
G. Kourmoulakis, A. Michail, I. Paradisanos, X. Marie, M. M. Glazov, B. Jorissen, L. Covaci, E. Stratakis, K. Papagelis, J. Parthenios, G. Kioseoglou
Summary: In this study, we investigate the impact of biaxial tensile strain on the optical properties of WS2 monolayers using micro-photoluminescence and Raman experiments. Our findings reveal a significant shift in the neutral exciton emission energy, as well as a decrease in circular polarization degree under the applied strain. Through experimental analysis, we separate the effect of strain-induced energy detuning and evaluate the pure effect of biaxial strain. Our analysis suggests that the suppression of circular polarization degree under biaxial strain is influenced by an interplay of energy and polarization relaxation channels, as well as changes in the exciton oscillator strength affecting the long-range exchange interaction.
APPLIED PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Dmitri R. Yakovlev, Scott A. Crooker, Marina A. Semina, Janina Rautert, Johannes Mund, Dmitry N. Dirin, Maksym V. Kovalenko, Manfred Bayer
Summary: This study investigates exciton-polaritons in solution-grown CsPbBr3 crystals by measuring circularly polarized reflection spectroscopy in high magnetic fields. Detailed quantitative information about the exciton-polariton parameters was obtained, showing that the exciton states can be described using a hydrogen-like model.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2023)
