Track topics on Twitter Track topics that are important to you
Graphene is emerging as a broadband optical material which can be dynamically tuned by electrostatic doping. However, direct application of grapheme sheets in optoelectronic devices is challenging due to its small thickness and the resultant weak interaction with light. By combining metal and graphene in a hybrid plasmonic structure, it is possible to enhance graphene-light interaction and thus achieve in situ control of the optical response. We show that the effective mode index of the bonding plasmonic mode in metal-insulator-metal (MIM) waveguides is particularly sensitive to the change in the optical conductivity of a graphene layer in the gap. By incorporating such MIM structures in optic antenna designs, we demonstrate an electrically tunable coupled antenna array on graphene with a large tuning range (1100 nm, i.e. 250 cm-1, nearly 20% of the resonance frequency) of the antenna resonance wavelength at the mid-infrared (MIR) region. Our device exhibits a 3dB cut-off frequency of 30 MHz, which can be further increased into the GHz range. This study confirms that hybrid metal-graphene structures are promising elements for high-speed electrically controllable optical and optoelectronic devices.
This article was published in the following journal.
Name: Nano letters
Optical fine-tuning was performed to reduce blue light leakage in a conventional reflective LCD and to obtain a reflective LCD with a better contrast ratio. Total light leakage in the dark state was e...
We propose and demonstrate a tunable photonic crystal nanolaser consisting of 1D periodic nanorods wrapped in deformable polydimethylsiloxane. In addition to low-threshold and long-term lasing stabili...
Plasmonic structures are known to affect the fluorescence properties of dyes placed in close proximity. This effect has been exploited in combination with single-molecule techniques for several applic...
In this work the preparation of flexible polymeric films with controlled electrical conductivity, light transmission and surface wettability is reported. A drop casted graphene oxide thin film is phot...
Broadband on-chip optical frequency combs (OFCs) are important for expanding the functionality of photonic integrated circuits. Here, we demonstrate a huge local optical nonlinearity enhancement using...
Treatment of neonatal jaundice is phototherapy with blue light at wavelength about 460 nm and irradiance > 30 uw/cm2/nm. Though, recent in vitro models have suggested that a wavelength of ...
We have developed a safe, non-contact, intra-operative guidance system to optimize tumor resection in neurosurgery. The Modulated Imaging (MI) is non-contact optical imaging technology dev...
The purpose of this investigation is to study the effectiveness of longer wavelength UVA1 (340-400nm) or shorter wavelength ultraviolet B [UVB] (290-320nm) irradiation in the treatment of ...
Traditional biopsy requires the removal, fixation, and staining of tissues from the human body. Its procedure is invasive and painful. Non-invasive in vivo optical biopsy is thus required,...
The macular pigment (MP) in humans consists of the yellow, blue-absorbing carotenoids lutein and zeaxanthin, which are contained in vegetables and fruits. The highest concentrations of lut...
Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard X-rays are the higher energy, shorter wavelength X-rays. Soft x-rays or Grenz rays are less energetic and longer in wavelength. The short wavelength end of the X-ray spectrum overlaps the GAMMA RAYS wavelength range. The distinction between gamma rays and X-rays is based on their radiation source.
The use of light interaction (scattering, absorption, and fluorescence) with biological tissue to obtain morphologically based information. It includes measuring inherent tissue optical properties such as scattering, absorption, and autofluorescence; or optical properties of exogenous targeted fluorescent molecular probes such as those used in optical MOLECULAR IMAGING, or nontargeted optical CONTRAST AGENTS.
A technique used to measure the rate of physiological activity plotted against wavelength of light. An action spectrum depicts the most effective wavelength of light (also known as spectral sensitivity) that is required for each specific process.
Products or parts of products used to detect, manipulate, or analyze light, such as LENSES, refractors, mirrors, filters, prisms, and OPTICAL FIBERS.
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
A diagnostic test is any kind of medical test performed to aid in the diagnosis or detection of disease. For example: to diagnose diseases to measure the progress or recovery from disease to confirm that a person is free from disease Clin...