111 research outputs found
Dataset for Nonlinear, Sensing and Switching Functionalities of Nano-optomechanical Metamaterials
Get PDFThis dataset supports the University of Southampton Doctoral Thesis:
Dimitrios Papas (2021) Nonlinear, Sensing and Switching Functionalities of Nano-optomechanical Metamaterials.
The dataset consists of 4 excel files containing data presented in Chapters 2, 3, 4 and 5 of the Thesis:
Chapter2Dataset.xlsx
Chapter3Dataset.xlsx
Chapter4Dataset.xlsx
Chapter5Dataset.xlsx
Each excel file contains separate sheets with data for each figure in the Thesis. Sheets are labelled with the figure number and panel they correspond to as well as a short description.
</span
Nonlinear, sensing and switching functionalities of nano-optomechanical metamaterials
No full textThis Thesis reports on the study of hybrid nano-optomechanical metamaterials, and their sensing, nonlinear and switching functionalities.I have constructed a dedicated apparatus for optical measurements of photonic metamaterials in vacuum during acoustic excitation. It is based on a fiberized inverted microscope setup operating at the wavelength of 1310 nm in both reflection and transmission modes.I have provided the first observation of fluctuations of optical properties of metamaterials due to thermal motion. In a plasmonic nanomechanical metamaterial thermal motion of mechanical components with an amplitude of a few hundreds of picometers leads to reflectivity fluctuations of the order of 0.1%. I have demonstrated the first tuning of mechanical eigenfrequencies of plasmonic nanomechanical metamaterials with light. Controlling the internal stress of the structure via light illumination allows tuning of the mechanical frequencies at which it can be efficiently driven. Eigenfrequency shifts of up to 19.5 % are measured for 7 μW of incident optical power. I have developed the first nanomechanical, metamaterial-based nanobolometer. Non-contact optical detection of infrared radiation is based on the detection of light scattered by two optically coupled nanomechanical beams providing spatial resolution of 400 nm, eigenfrequency shift per unit of incident optical power (responsivity) of 2-3%/μW with a noise equivalent power of 3-5 nW/Hz1/2. I have demonstrated a new type of volatile optical bistability in a resonant hybrid nanooptomechanical device. The bistable function has been demonstrated on a pair of anchored beams decorated with plasmonic metamolecules. The nonlinearity resides in the mechanical properties of the beams that can be driven to a bistable response by acoustic signals modulated at their natural mechanical resonances. Optical switching between the two mechanically stable states is demonstrated with 6 μW of incident optical power and the bistable states are sustained and controllable by about a pW of mechanical power delivered to a beam. Overall, hybridization of mechanically and optically resonant structures can provide sensing and switching functionalities based on their mechanical properties and nonlinear response.<br/
Optomechanical metamaterial nanobolometer
No full textBolometers are detectors of electromagnetic radiation that usually convert the radiation-induced change of temperature of the detector into electric signals. Temperature-dependent electrical resistance in semiconductors and superconductors, the thermoelectric effect in thermocouples and the pyroelectric effect of transient electric polarization of certain materials when they are heated or cooled are among the underlying physical phenomena used in bolometers. Here, we report that the dependence of the fundamental frequency of a nanowire string detected via scattering of light on the string can be used in a bolometer. Arrays of such nanowires can serve as detectors with high spatial and temporal resolution. We demonstrate a bolometer with 400 nm spatial resolution, 2-3 μs thermal response time and optical power detection noise floor at 3-5 nW/Hz^0.5 at room temperature
Optical metamaterial reconfigured with sound
No full textWe demonstrate that ultrasound vibrations cause linear and nonlinear changes of optical properties of nanomechanical metamaterials that are comparable to the magnitude of the optical properties themselves. We observe up to 73% linear acousto-optical reflectivity modulation in a metamaterial of only 100 nm thickness and substantial nonlinear acoustooptical modulation up to the sixth order. Our results indicate that acousto-optical metamaterials enable the miniaturization of acousto-optical technology by orders of magnitude and acoustooptics with extreme nonlinearity
Hybrid bistability in nano-opto-mechanical metamaterial
No full textA nanowire array decorated with plasmonic resonators acts as optically bistable device. The optical properties of this metamaterial exhibit hysteresis and bistability when it is driven by a piezo actuator across its mechanical resonance frequency
Acoustically driven photonic metamaterials
No full textWe modulate the optical properties of nanomechanical reconfigurable metamaterials with ultrasound. Resonant vibration of the elements of the metamaterial array leads to pronounced changes in its optical properties
Bistability of optical response of plasmonic nanowire device at microwatt power levels
No full textA profound optical bistability in light scattering is observed in a pair of oscillating nanowires decorated with plasmonic patterns. The response becomes bistable at only a few μW of incident optical power, which is facilitated by coupling between the plasmonic and the highly nonlinear mechanical subsystems of the nanostructure
Nanomechanical bistability in photonic metamaterial
No full textA nanowire array decorated with plasmonic resonators acts as optically bistable device. The optical properties of this metamaterial exhibit hysteresis and bistability when it is driven by a piezo actuator across its mechanical resonance frequency
Dataset for Optomechanical metamaterial nanobolometer
No full textThis research dataset should be interpreted and understood in the context of the corresponding manuscript, which has been published in APL Photonics with DOI: 10.1063/5.0073583. All relevant information regarding the dataset, how it was obtained and its context is contained in the manuscript. The data correspond to the data shown in the figures of the manuscript.</span
Playing the metamaterial guitar with light and ultrasound
No full textThe ultimate goal of metamaterials research may be described as arbitrary control over material properties at any point in time and space. Fundamentally, this requires the ability to modify a metamaterial structure with sub-wavelength spatial resolution. Here we demonstrate dynamic control over metamaterial properties beyond the diffraction limit based on acoustic resonances and electromagnetic resonances of nanomechanical metamaterials
- …
