Papers by Emmanuel Bigler
This paper presents the design of the Surface Transverse Wave (STW) resonators on langasite. The ... more This paper presents the design of the Surface Transverse Wave (STW) resonators on langasite. The empirical values of coupling-of-modes (COM) parameters are shown, and a comparison between the theoretical resonator responses computed with these values and measured responses is performed. The resonance and antiresonance frequencies are evaluated as a function of the thickness of metal electrodes. Results for STW resonator response on langasite exhibit very important differences with respect to similar STW devices built on ST and AT quartz. Finally, temperature sensitivity of the STW langasite resonators has been measured and compared to theoretical predictions based on various sets of published material constants
2008 IEEE International Frequency Control Symposium, 2008
In this paper, new experiments have been carried out on LGS crystal to highlight the existence of... more In this paper, new experiments have been carried out on LGS crystal to highlight the existence of temperature compensated cuts for flexure vibration. The micro-resonators are square cross section tuning forks whose arms are vibrating in flexure-mode with clamped-free boundary conditions. Frequency versus temperature behaviors have been measured for several cut angles. The results of our experiments show that there is a first order temperature-compensated cut for Langasite crystal resonators vibrating in flexion at room temperature. I.
2009 IEEE International Frequency Control Symposium Joint with the 22nd European Frequency and Time forum, 2009
ABSTRACT Quartz length-extension resonators have already been used to get atomically-resolved ima... more ABSTRACT Quartz length-extension resonators have already been used to get atomically-resolved imaging by frequency-modulation atomic force microscopy. New piezoelectric materials such as Langasite could be appropriate for this application. Theoretical study is reported on length extension resonators in this material. In this paper, an attempt to fabricate micro resonators in Langasite temperature-compensated cuts is prospected. The pointed tip of the micromachined cantilever can be used for atomic force microscopy applications.
2019 Joint Conference of the IEEE International Frequency Control Symposium and European Frequency and Time Forum (EFTF/IFC), 2019
We present our latest results obtained with a surface-electrode ion trap designed for optical fre... more We present our latest results obtained with a surface-electrode ion trap designed for optical frequency metrology. A prototype trap, based on a simple geometry realized on a printed-circuit board, has been successfully used to trap single Yb $^{\mathbf {+}}$ ions. Our long-term goal is the realization of a compact single-ion optical clock.
2006 IEEE International Frequency Control Symposium and Exposition, 2006
ABSTRACT The goal of this paper is to investigate the possibility of temperature-compensated cuts... more ABSTRACT The goal of this paper is to investigate the possibility of temperature-compensated cuts for both kinds of vibrations in Langasite resonators. We propose theoretical and experimental investigations of vibrating beam resonators with a rectangular cross-section in extensional and flexural modes for Langasite. Measures of frequency-temperature effects in beam vibrating in length extension are given
Solid State Sciences, 2010
The present paper reviews and compares the properties of vibrating beam resonators in length-exte... more The present paper reviews and compares the properties of vibrating beam resonators in length-extensional, flexural and cylindrical-torsional modes; resonators are designed and built with new piezoelectric materials: Gallium orthophosphate (GaPO 4), Langasite (LGS) and Langatate (LGT). Their characteristics are compared with the results obtained with the same structures built in classical Quartz crystal. For all 3 new crystals, temperature-compensated cuts have been found for length-extensional and flexural modes by a theoretical analysis. Experiments have been made on test beams fabricated by conventional precision lapping/machining and photolithography to deposit electrodes. The existence of temperature-compensated cuts for length-extensional resonators is experimentally confirmed. The possibilities of using temperature-compensated cylindrical resonators in the torsional modes are analysed and their temperature sensitivity is computed.
2009 IEEE International Ultrasonics Symposium, 2009
ABSTRACT Scanning microdeformation microscopy (SMM) is a near field microscopy in the mesoscopic ... more ABSTRACT Scanning microdeformation microscopy (SMM) is a near field microscopy in the mesoscopic domain. Such a microscope has become an alternative to the high resolution acoustic microscope that operates at very high frequencies. SMM is based on a vibrating contact tip and piezoelectric detection. The lateral resolution is essentially related to the tip diameter. Classically, the SMM sensor is obtained by a complex mounting process. The tip is glued on a Si cantilever driven by a piezoelectric ceramic. Piezoelectric crystal is an alternative to get a monolithic vibrating cantilever. Quartz crystal, which is the most often used piezoelectric material, can be advantageously replaced by Langasite crystal because of its higher piezoelectric coefficients and its better temperature behaviour.
We show here how SCHEIMPFLUG’s rule can be found by an elementary ray tracing procedure based on ... more We show here how SCHEIMPFLUG’s rule can be found by an elementary ray tracing procedure based on common rules of image formation in a thin positive lens.
2007 IEEE International Frequency Control Symposium Joint with the 21st European Frequency and Time Forum, 2007
ABSTRACT In this paper, the possibility of temperature-compensated cuts for different kinds of vi... more ABSTRACT In this paper, the possibility of temperature-compensated cuts for different kinds of vibrations in Langatate resonators is investigated. Theoretical investigations of vibrating beam resonators with a rectangular cross-section in extensional, flexural and torsional modes are given.
The Journal of the Acoustical Society of America, 2001
c onique et Pie ´zoe d ´lectricite c ´,E e ´cole Nationale Supe ´rieure d'Inge ´nieurs f de Micro... more c onique et Pie ´zoe d ´lectricite c ´,E e ´cole Nationale Supe ´rieure d'Inge ´nieurs f de Microme ´canique g et des Microtechniques, 26 Chemin de l'E ´pitaphe, h
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2005
Flexural modes are the basic vibrating mode of tuning forks used in quartz wrist watches; they al... more Flexural modes are the basic vibrating mode of tuning forks used in quartz wrist watches; they also can be used as the basis for sensors. Very little work, if any, has been done for vibrating beam resonators in GaPO4. In this paper, the possibility of temperature-compensated cuts in GaPO4 is investigated for length-extensional and flexural vibrating modes. A theoretical investigation of rectangular cross-section GaPO4 vibrating beam resonators is accomplished by analytical methods. Modeling temperature effect is achieved by the approximate but classical method in which the effective elastic constants, beam dimensions, and crystal mass density are varied as a function of temperature. Temperature-compensated cuts are given in GaPO4 for length-extensional and flexural modes. Some temperature-compensated cuts of GaPO4 exhibit inversion points at high temperatures.
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 1997
This paper discusses the role of gestural vs auditive components of a piano performance when the ... more This paper discusses the role of gestural vs auditive components of a piano performance when the performer is prompted to portray a specific emotion. Pianist William Westney was asked to perform a short passage from a specific piece of music 6 times, 3 times without making any deliberate changes, and 3 times where the music was intended to portray the emotions happy, sad and angry, respectively. Motion-capture data from all of the performances was recorded alongside the audio. We analyze differences in the data for the different emotions, both with respect to the size and shape of the pianist's movements and with respect to the sonic qualities of the performances. We discuss probable explanations of these differences. Although differences are found in both the gestural and auditive components of the performance, we argue that the gestural components are of particular importance to the performer's shaping of a musical expression.
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2007
This paper shows that first order temperature compensated cut exists in Langasite rectangular cro... more This paper shows that first order temperature compensated cut exists in Langasite rectangular cross-section beam vibrating in length extensional mode. Theoretical and experimental investigations of frequencytemperature effects are given.
Comptes Rendus de l'Académie des Sciences - Series IV - Physics, 2000
Reçu le 21 juillet 1999, accepté le 9 mai 2000) Résumé. Des résonateurs à ondes élastiques transv... more Reçu le 21 juillet 1999, accepté le 9 mai 2000) Résumé. Des résonateurs à ondes élastiques transverses sur plaque fine de quartz ont été optimisés grâce à une étape de fabrication spécifique dans le but d'améliorer leur coefficient de qualité et de minimiser leurs pertes d'insertion. Des mesures systématiques ont été effectuées, mettant en évidence l'efficacité de l'approche proposée. On montre ainsi la possibilité de fabriquer des résonateurs fonctionnant dans la gamme de fréquence 100-250 MHz et présentant des produits coefficients de qualité-fréquence nettement supérieurs à 10 13 , ce qui correspond à dépasser l'état de l'art des résonateurs à ondes de surface. © 2000 Académie des sciences/Éditions scientifiques et médicales Elsevier SAS résonateurs / ondes de surface / ondes de surface transverse / facteur de qualité / modes de plaque / R.I.E.
Applied Optics, 1985
ABSTRACT
We show here how pure geometrical considerations with an absolute minimum of algebra will yield t... more We show here how pure geometrical considerations with an absolute minimum of algebra will yield the solution for the position of slanted planes defining the limits of acceptable sharpness (an approximation valid for distant objects) for Depth-of-Field (DOF) combined with SCHEIMPFLUG's rule. The problem of Depth-of-Focus is revisited using a similar approach. General formulae for Depth-Of-Field (DOF) are given in appendix, valid in the close-up range. The significance of the circle of least confusion, on which all DOF computations are based, even in the case of a tilted view camera lens and the choice of possible numerical values are also explained in detail in the appendix. 1 Derivation of the position of slanted limit planes of acceptable sharpness 1.1 Starting with reasonable approximations Consider a situation where we are dealing with a pair of corresponding slanted object and image planes according to SCHEIMPFLUG's rule (fig. 4), and let us first assume a few reasonable approximations: 1. first we neglect the fact that the projection of a circular lens aperture on film, for a single, out of focus point object, will actually be an ellipse and not a circle. This is well explained by Bob WHEELER [1] who shows, after a complete rigorous calculation, that this approximation is very reasonable in most practical conditions. 2. second we consider only far distant objects; in other words we are interested to know the position of limit surfaces of sharpness far from the camera, i.e. distances or ¡ much greater than the focal length ¢. We'll show that those surfaces in the limit case are actually planes, the more rigorous shape of these surfaces for all object-to-camera distances can be found in Bob WHEELER's paper, in Leslie STROEBEL's book [5], and here in the appendix.
Flexural modes of Quartz crystal beams are widely used for wrist watch resonators and vibrating b... more Flexural modes of Quartz crystal beams are widely used for wrist watch resonators and vibrating beam resonators for sensors. Torsional modes of quartz have also been studied even if less applications have been developed. We present here a first evaluation of both flexural and torsional modes of rectangular cross-section vibrating bars of Gallium Orthophosphate (GaPO4). An analytical model of vibrating beam resonators in flexural and torsional modes is built and validated by comparison with Quartz data on similar structures. Temperature effects are introduced by the approximate but classical method of varying effective material constants, beam dimensions and crystal mass density versus temperature. Temperature-compensated GaPO4 orientations of vibrating beam in torsional modes are predicted. Introduction The piezoelectric crystal of gallium orthophosphate (GaPO4) is new quartz homeotypic crystal. Due to the lack of the α−β phase transition most material properties are stable up 970°C...
Applications of SAW devices to physical sensors have already reached industrial maturity in the f... more Applications of SAW devices to physical sensors have already reached industrial maturity in the field of passive physical sensors (e.g. wireless torque sensors) the last development being related to the capability of SAW devices to offer remote readout by a radio-frequency link. A review of existing simulation methods is used to derive the sensitivity of SAW devices to temperature or mechanical stress is presented. The emphasis is put on perturbation methods based on Tiersten and Sinha theory. Applications including current commercially available SAW physical sensors will be discussed. Introduction Starting from the very high performance of oscillators based on Bulk Acoustic Wave (BAW) and Surface Acoustic Wave devices (SAW), the idea to apply an external physical parameter to the piezoelectric resonator was investigated first in order to minimise environment effects on high stability clocks ; quartz and now some new piezoelectric materials offer naturally compensated crystalline or...
A model predicting the influence of various design parameters on fundamental properties such as r... more A model predicting the influence of various design parameters on fundamental properties such as resonant frequency, Q factor, and insertion losses is presented. STW resonators offer several advantages over conventional Rayleigh wave SAW (Surface Acoustic Wave) resonators, one of the most interesting advantages being higher operating frequencies (+60 percent) for given geometrices of the transducers and reflectors. A model to compute the resonant frequency of a three grating STW resonator is presented and and the influence of important design parameters, cavity length, metal thickness, grating periodicities, and finger to gap ratio is discussed. Starting from first experimental results, obtained in metal strip (37 deg Y rotated) quartz STW resonators at 500 MHz, new devices at 1 GHz were fabricated and tested. Experimental results are presented and discussed.
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Papers by Emmanuel Bigler