ΘΕΜΑ: Παρουσίαση PhD Τσώτσης Παναγιώτης ΤΕΤΥ ΑΠΟΣΤΟΛΕΑΣ: Charalampos Stratigis [mailto:stratigis@xxxxxxxxxxxxxxxx] Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής του κ. Τσώτση Παναγιώτη (Σύμφωνα με το άρθρο 12 του Ν. 2083/92) Την Παρασκευή 20 Φεβρουαρίου 2015 και ώρα 10:00 στην αίθουσα Φ2 στο κτίριο του Τμήματος Φυσικής θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής του υποψήφιου διδάκτορα του Τμήματος Επιστήμης και Τεχνολογίας Υλικών κ. Τσώτση Παναγιώτη με θέμα: «Ανάπτυξη και Mελέτη Kαινοτόμων Πολαριτονικών Διατάξεων» «Fabrication and Study of Novel Polaritonic Devices» ABSTRACT Polaritons are bosonic quasiparticles resulting from the strong coupling between photons and excitons in a solid-state semiconductor microcavity. Their exotic properties arising from their light and matter composition, such as short lifetime and strong nonlinear interactions, constitutes an ideal theoretical and experimental platform for studying out-of-equilibrium fundamental physics properties as well as more applied quantum optics phenomena and possible applications. In this thesis, two themes are treated which are strongly related with realistic applications. In the first part, we realize ultralow threshold polariton lasing regime under optical pumping in a high finesse planar microcavity. Temperature dependence and transition between lasing in the strong and weak coupling regime is investigated. Notably polariton lasing regime is found to be restricted to temperatures below 50K in GaAs microcavity system. Following the realization of polariton lasing device under non-resonant optical pumping, efforts have been directed towards the demonstration of an electrically injected polariton laser. In the second part, we introduce an electrically driven scheme to tune the polariton condensate energy. In contrast to the expected energy redshift, we observed an energy blueshift of polariton condensate caused by controlled Rabi splitting reduction due to tunneling-induced charge buildup in neighboring QWs. This ability to tune the polariton condensate energy brings within reach the realization of voltage-controlled polariton condensate devices and variable-wavelength sources of coherent light. |
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