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This paper demonstrates a 160 nm thick first- and third-order antisymmetric mode Lithium Niobate resonator. The presented device maintains feature sizes on the order of micrometers by thinning the piezoelectric resulting in a first-order mode at 11.77 GHz through direct scaling of state-of-the-art design approaches. Thinning leverages an Argon-based low-power physical etch, with attention paid specifically to surface roughness. The fabricated device demonstrates a first-order antisymmetric series resonant frequency of 11.77 GHz with an electromechanical coupling of 23.6% and a mechanical quality factor of 148 for a Figure of Merit of 35.1. In addition, the resonator's third-order antisymmetric mode achieves an electromechanical coupling of 3.7% and a mechanical quality factor of 66 at a frequency of 34.7 GHz.

In this work, we present the low-loss acoustic delay lines (ADLs) at 5 GHz, using the first-order antisymmetric (A1) mode in 128° Y-cut lithium niobate thin films. The ADLs use a single-phase unidirectional transducer (SPUDT) design with a feature size of quarter acoustic wavelength. The design space is analytically explored and experimentally validated. The fabricated miniature A1 ADLs with a feature size of show a high operating frequency at 5.4 GHz, a minimum insertion loss (IL) of 3 dB, a fractional bandwidth (FBW) of 1.6%, and a small footprint of 0.0074 mm 2 . The low IL and high operating frequency have significantly surpassed the state-of-the-art performance of ADLs. The propagation characteristics of A1 acoustic waves have also been extracted. The demonstrated designs can lead to low-loss and high-frequency transversal filters for future 5G applications in the sub-6-GHz bands.

We present a wideband acousto-optic modulator on a suspended thin-film lithium niobate where both light and acoustic waves are guided simultaneously. The modulator has a center frequency of 1.9 GHz and bandwidth of 70 MHz. © 2021 OSA.

IIn this work, we present first-order antisymmetric (A1) mode resonators in 128° Y-cut lithium niobate (LiNbO 3 ) thin films with electromechanical coupling coefficients (k 2 ) as large as 46.4%, exceeding the state-of-the-art. The achievable k 2 of A1 in LiNbO 3 substrates of different orientations is first explored, showing X-axis direction in 128° Y-cut LiNbO 3 among the optimal combinations. Subsequently, A1 resonators with spurious mode mitigation are designed and fabricated. In addition to the large k 2 , the implemented devices show a maximum quality factor (Q) of 598 at 3.2 GHz. Upon further optimization, the reported platform can potentially deliver a wideband acoustic-only filtering solution in 5G New Radio.

Risiken aus alpinen Naturgefahren beschreiben Mensch-Umwelt Systeme die ständigem Wandel unterliegen. Diese Arbeit fokussiert sich auf den Wandel des gesellschaftlichen Umgangs mit Risiken aus alpinen Naturgefahren. Derzeit gewinnen Kommunikation und Partizipation in öffentlichen Belangen im Zuge gesamtgesellschaftlicher Entwicklungen zunehmend an Bedeutung. Im Lichte dessen gilt es den gesellschaftlichen Umgang mit Risiken aus alpinen Naturgefahren nachhaltig mitzugestalten. Im Alpenraum ist die historische Entwicklung des Umgangs mit Risiken aus alpinen Naturgefahren seit ca. 1850 gekennzeichnet durch drei aufeinander aufbauende Paradigmen. Das Paradigma „Schutz vor Naturgefahren“ war in etwa hundert Jahre lang prägend wirksam. Es wurde in der zweiten Hälfte des letzten Jahrhunderts durch „Gefahrenmanagement“ abgelöst. Gegenwärtig bestimmt „Risikomanagement“ die Praxis des Umgangs mit Risiken aus alpinen Naturgefahren. „Risiko Governance“ steht derzeit als zukünftiges Paradigma in Diskussion. Kommunikation und Beteiligung stellen zentrale Elemente von allgemeinen Risiko Governance Konzepten dar. In dieser Arbeit wird die Tauglichkeit allgemeiner Risiko Governance Konzepte auf den Kontext von Risiken aus alpinen Naturgefahren evaluiert. Am Beispiel der Gefahrenzonenplanung in Südtirol werden Kommunikationsstrukturen auf interner und externer Ebene analysiert und hinsichtlich ihrer Zukunftsfähigkeit bewertet. Empirische Untersuchungen mittels qualitativer und quantitativer Methoden bieten die Grundlage dazu. Risiko Governance wird hier als zukunftsweisendes Konzept gewertet, das auch auf den Umgang mit Risiken aus alpinen Naturgefahren angewendet werden kann. Bestehende Kommunikations- und Verwaltungsstrukturen gilt es hierzu jedoch grundlegend zu hinterfragen und anzupassen. Für Südtirol werden Vorschläge sowohl zur unmittelbaren Verbesserung der Kommunikation in der Gefahrenzonenplanung wie auch zu tiefgreifenden organisationstrukturellen Anpassungen hin zu Risiko, Risks from alpine hazards represent human-environmental systems that are subject to constant change. This contribution focusses on change processes in the societal handling of mountain risks. In the course of recent social developments communication and participation in public issues are gaining importance. Accordingly, the handling of mountain risks must be shaped in a sustainable manner. Approximately from 1850 onwards, the historical development of the dealing with mountain risks in the Alps can be characterized by three paradigms that build upon each other. “Hazard protection” served as a paradigm for approximately 100 years. It was succeeded by the paradigm of “hazard management” in the second half of the 20th century. Currently, the paradigm of “risk management” is widely applied and it shapes the societal handling of mountain risks. Meanwhile, “Risk governance” is discussed as a future paradigm. Communication and participation are central elements in general risk governance frameworks. Here, the suitability of general risk governance frameworks to the specific context of mountain risks is evaluated. Hazard zone planning in South Tyrol serves as a case study therefore. The current communication structures on internal and external level are analysed and assed concerning their appropriateness to risk governance concepts. This is based on quantitative and qualitative empirical studies. Here, risk Governance is evaluated as a future-orientated concept that is also applicable to mountain risks. For the application of risk governance in a mountain risk context, existing administrative and communication structures have to be scrutinized and fundamentally adapted. For South Tyrol, improvements are proposed on two levels: direct improvements of communication in hazard zone planning, as well as fundamental adaptations of the organisation structures towards the application of risk governance. The core of the content of this contribution is made of four English articles., Steffen Link, Enth. u.a. 4 Veröff. d. Verf. aus den Jahren 2010 - 2014 . - Zsfassung in dt. und in engl. Sprache, Text teilw. in dt. und teilw. in engl. Sprache, Innsbruck, Univ., Diss., 2015, OeBB, (VLID)336581