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This thesis focuses on electron transport in semiconductor InAs/InP and InSb nanowire quantum devices. However, first the temperature dependence of classical charge transport in InSb nanowire field-effect transistors, FETs, is characterized, using InAs nanowire FETs as a reference. We find that the InSb FETs, in the same way as InAs FETs, are n-type with good current saturation and low voltage ope
14 oktober 2026 08:30 till 22:00 | Konferens The 2026 Synergy Meeting of the Lund University profile area Light & Materials will focus on the theme “Sensing and Sensors” and is organised jointly by Lund Laser Centre and NanoLund. Stay tuned for updates!Preliminary programme: 8:30 Coffee and registration8:55 The programme starts:Introduction Light & Materials, Lund Laser Centre, NanoLund. Invited t
https://www.lu.se/evenemang/light-materials-synergy-meeting-2026 - 2026-09-06
We report preliminary experimental and computational studies of the temporal evolution of the harmonics, generated in xenon, by 50-ps pulses from a Nd: YLF laser, amplified in Nd: glass amplifiers, and focused to produce intensities in the range 1013--5 {\texttimes} 1013 W cm{\textminus}2. Measurements were made of the temporal profiles of the seventh- and ninth-order harmonics using a specially m
The exact diagonalization technique is used to study many-particle properties of interacting electrons with spin, confined in a two-dimensional harmonic potential. The single-particle basis is limited to the lowest Landau level. The results are analysed as a function of the total angular momentum of the system. Only at angular momenta corresponding to the filling factors 1, 1/3, 1/5, etc is the sy
In 2015 Jonatan Bohr Brask et al. showed that steady-state entanglement could be generated in two interacting qubits incoherently coupled to thermal baths of different temperatures [1]. This thesis is an attempt to re-evaluate their findings with the hope that a slightly different approach and system can help further our understanding of this not yet well understood phenomena. A Lindblad master eq
Semiconductor nanostructure based devices provide new opportunities for contributing to a sustainable energy usage. This includes harvesting of energy (solar cells) and saving of energy, e.g. in lighting (light-emitting diodes, LEDs) and transfer of energy (power devices). However, development and improvement of nanostructure devices requires thorough characterization and understanding on a singleSemiconductor nanostructure based devices provide new opportunities for contributing to a sustainable energy usage. This includes harvesting of energy (solar cells) and saving of energy, e.g. in lighting (light-emitting diodes, LEDs) and transfer of energy (power devices). However, development and improvement of nanostructure devices requires thorough characterization and understanding on a single
The possibility of engineering artificial Kitaev chains in arrays of quantum dots coupled via narrow superconducting regions has emerged as an attractive way to overcome the disorder issues that complicate the realization and detection of topological superconducting phases in other platforms. Although a true topological phase would require long chains, a two-site chain realized in a double quantum
Ljus består av elektromagnetiska vågor som pulserar genom universum med olika frekvenser. Vanligt ljus, som det som kommer från solen och från våra lampor, innehåller ett spektrum av många olika frekvenser. De olika vågornas toppar och dalar svänger inte heller i takt, utan är förskjutna i förhållande till varandra. I laserljus däremot, svänger alla vågor samtidigt upp och ner och med samma frekveThis thesis adresses modeling of quantum cascade lasers using non-equilibrium Green’s functions. Focus lies on the quantitative modeling of the gain when the systems are exposed to strong laser fields, as under realistic opertional conditions. In the first part, an introduction to the general concepts is provided, together with a discussion on approximate analytic expressions. The second part cons
The interplay between superconductivity and the Kondo effect has stimulated significant interest in condensed matter physics. They compete when their critical temperatures are close and can give rise to a quantum phase transition that can mimic Majorana zero modes. Here, we have fabricated and measured Al-InSb nanowire quantum dot-Al devices. In the Kondo regime, a supercurrent-induced zero-bias c
Majorana modes can be engineered in arrays where quantum dots (QDs) are coupled via grounded superconductors, effectively realizing an artificial Kitaev chain. Minimal Kitaev chains, composed by two QDs, can host fully localized Majorana modes at discrete points in parameter space, known as Majorana sweet spots. Unlike grounded superconductors, where the superconducting phase is a conserved quantu
Measuring the thermopower of a confined quantum system reveals important information about its excitation spectrum. Our simulations show how this kind of transport spectroscopy is able to extract a clear signal for the onset of Wigner localization in a nanowire segment. This demonstrates that thermopower measurements provide a tool for investigating complex many-body quantum effects, which is less
The three superdeformed (SD) bands in Ce-132 and the two SD bands in Ce-131 have been extended to higher spin, following experiments with the EUROBALL IV spectrometer. The two SD bands in Ce-131 have been linked together. However, despite the relatively high population intensity of the bands (up to 5% of the respective channel), it has not been possible to unambiguously link any of the five SD ban
In a large variety of disciplines, fundamental studies often straddle in self-referential situations, in need of relativization to language and complementaristic resolution. In such attempts, the languages at play are hardly visible themselves. Only shadows of language, somewhat characteristic of the various disciplines, become visible and tractable. We select two domains, quantum mechanics and cy
Charge separation dynamics after the absorption of a photon is a fundamental process relevant both for photosynthetic reaction centers and artificial solar conversion devices. It has been proposed that quantum coherence plays a role in the formation of charge carriers in organic photovoltaics, but experimental proofs have been lacking. Here we report experimental evidence of coherence in the charg
We present an experimental characterization of the process of coherent harmonic generation in single-pass free electron lasers. The harmonic radiation is obtained by seeding the electron beam stored in the Elettra storage ring with a Ti:sapphire laser. Different methods for generating harmonics are compared between them, and a detailed characterization of the emitted light is performed for differe
Regulatory T cells (Tregs) differentiate in the thymus, but the mechanisms that control this process are not fully understood. We generated a comprehensive quantitative and differential proteome of murine Tregs and conventional T cells. We identified 5225 proteins, 164 of which were differentially expressed in Tregs. Together with the comparative analysis of proteome and gene expression data, we i
