Optical Multistability in the Metal Nanoparticle-Graphene Nanodisk-Quantum Dot Hybrid Systems.

Hybrid nanoplasmonic systems can provide a promising platform of potential nonlinear applications due to the enhancement of optical fields near their surfaces in addition to the control of strong light-matter interactions they can afford. We theoretically investigated the optical multistability of a probe field that circulated along a unidirectional ring cavity containing a metal nanoparticle-graphene nanodisk-quantum dot hybrid system; the quantum dot was modeled as a three-level atomic system of Lambda configuration interacting with probe and control fields in the optical region of the electromagnetic spectrum. We show that the threshold and degree of multistability can be controlled by the geometry of the setup, the size of metal nanoparticles, the carrier mobility in the graphene nanodisk and the detunings of probe and control fields. We found that under electromagnetically-induced transparency conditions the system exhibits enhanced optical multistability with an ultralow threshold in the case of two-photon resonance with high carrier mobility in the graphene nanodisk. Moreover, we calculated the limits of the controllable parameters within which the switching between optical multistability and bistability can occur. We show that our proposed hybrid plasmonic system can be useful for efficient all-optical switches and logic-gate elements for quantum computing and quantum information processing.

[Postmenopausal lichen planopilaris also known as fibrosing frontotemporal alopecia Kossard : An evidence-oriented practical guide to treatment from the University of the Saarland, Hair Research Center of the Dr. Rolf M. Schwiete Foundation]. / Postmenopausaler Lichen planopilaris alias fibrosierende frontotemporale Alopezie Kossard : Ein evidenzorientierter "practical guide to treatment" des Haarforschungszentrums der Dr. Rolf M. Schwiete Stiftung an der Universität des Saarlandes.

Postmenopausal lichen planopilaris (PLPP), also known as fibrosing frontotemporal alopecia Kossard (FFAK), is a not uncommon inflammatory scalp disease affecting approximately 5% of patients at specialized hair centers. The overall incidence of sporadic occurrence is believed to be just under 1% in the older, predominantly female, general population. Since the disease is often undiagnosed, it is statistically likely to be underrepresented. It especially occurs in postmenopausal women who are in the 6th and 7th decade of life (90%), but also in about 10% of premenopausal women, and in men it is documented only in isolated cases. The result is a permanent scarring hair loss accentuated at the front hairline with backward movement towards the neck mostly accompanied by a typical loss of the eyebrows. The disease therefore often leads to significant mental distress and social anxiety in those affected. This is the basis for a compelling need to develop evidence-based therapeutic concepts. While numerous retrospective case series have characterized the phenomenology of FFAK very well, to date there are no randomized controlled trials on evidence-based therapy. Here, we present the Homburger Evidence-Oriented Therapy Algorithm, which is oriented along the available case series evidence: It may (1) serve as a therapy guide for practice and (2) can be used as a basis for working out reliable data based on study evidence. The article contains detailed practical information on photo documentation, biopsy and histological processing up to the practical implementation of, for example, intralesional steroid therapy as well as information on selection criteria for suitable systemic therapies.