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News On Plasmonics

In these days, the Journal of Scientific Reports published a new paper entitled as “Angular surface plasmon resonance‑based sensor with a silver nanocomposite layer for effective water pollution detection”

For sensing various samples of polluted water and various sodium chloride concentrations using an angular surface plasmon resonance (ASPR), we have introduced a conventional structure and a hybrid heterostructure in the current research. The suggested structures are composed of silver metal, dielectric layers, silver nanocomposite, and a sensing medium. The refectance spectra of all structures in the visible region were obtained through the utilization of the transfer matrix method by using the angular interrogation method depending on the Kretschmann confguration. Through our findings, five substrate parameters have been optimized to attain the utmost level of sensitivity across all structures: the thickness of Ag-metal, the type and thickness of dielectric materials, the host material type and the volume fraction of nanoparticles for the nanocomposite layer. In this regard, the suggested sensor provides excellent performance with a sensitivity of 448.1°/RIU, signal-to-noise ratio of 0.787, sensor resolution of 0.284°, and figure of merit of 78.766 RIU−1. Therefore, we believe that the introduced design of our ASPR sensor presents a good candidate for an accurate and effcient detection of low concentrations of contaminated water and sodium chloride as well.

News On Plasmonic Biosensors

In these days, the journal of Sensors published a new paper entitled as “New Biosensor for Determination of Neuropilin-1 with Detection by Surface Plasmon Resonance Imaging“

Abstract: Neuropilin-1 is transmembrane protein with soluble isoforms. It plays a pivotal role in both physiological and pathological processes. NRP-1 is involved in the immune response, formation of neuronal circuits, angiogenesis, survival and migration of cells. The specific SPRI biosensor for the determination of neuropilin-1 was constructed using mouse monoclonal antibody that captures unbound NRP-1 form body fluids. The biosensor exhibits linearity of the analytical signal between 0.01 and 2.5 ng/mL, average precision value 4.7% and recovery between 97% and 104%. The detection limit is 0.011 ng/mL, and the limit of quantification is 0.038 ng/mL. The biosensor was validated by parallel determination of NRP-1 in serum and saliva samples using the ELISA test, with good agreement of the results.

News On Bloch Waves

Strong driving to realize super-Bloch oscillations

Full coherent control of wave transport and localization is a long-sought goal in wave physics research, which encompasses many different areas from solid-state to matter-wave physics and photonics. One among the most important and fascinating coherent transport effects is Bloch oscillation (BO), which refers to the periodic oscillatory motion of electrons in solids under a direct current (DC)-driving electric field. Super-Bloch oscillations (SBOs) are giant oscillatory motions achieved by applying simultaneously detuned DC- and AC-driving electrical fields. Considered amplified versions of BOs, SBOs receive less attention than ordinary BOs mainly because their experimental observations are more challenging and require a much longer particle coherence time.

One unique feature of SBOs is the existence of coherent oscillation inhibition through an AC-driving renormalization effect, which manifests as the localization of an oscillation pattern with a vanishing oscillation amplitude. Dubbed the “collapse” of SBO, this interesting phenomenon typically occurs in the strong AC-driving regime, which hasn’t been reached in previous experiments of SBOs based on electronic and other systems. All present theoretical and experimental studies on SBOs have been limited to the simplest sinusoidal AC-driving cases, so the SBO collapse under more general AC-driving formats, and the ability to harness SBOs for flexible coherent wave manipulation, also remain unexplored.

Congratulations on Publishing our Selected Paper in the MDPI book

Congratulations on publishing our selected article in the MDPI book “1D and 2D Nanomaterials for Sensor Applications”

Our selected Paper: “Colorimetric Plasmonic Hydrogen Gas Sensor Based on One-Dimensional Nano-Gratings“

Majid Zarei, Seyedeh M. Hamidi and K. -W. -A. Chee

MDPI Books offers quality open access book publishing to promote the exchange of ideas and knowledge in a globalized world. MDPI Books encompasses all the benefits of open access – high availability and visibility, as well as wide and rapid dissemination. With MDPI Books, you can
complement the digital version of your work with a high quality printed counterpart.

https://www.mdpi.com/journal/crystals/special_issues/1D_2D_Nanomaterials_Sensor_Applications

Congratulations for Our New Paper in Journal of Measurment

Detection of gentamicin in water and milk using chitosan-ZnS-Au nanocomposite based on surface plasmon resonance imaging sensor
Amir Reza Sadrolhosseini, Seyedeh Mehri Hamidi⁎, Younes Mazhdi

The detection of antibiotics in milk, water, and agricultural products is a topic of interest for health care and environmental protection. Some antibiotics such as oxytetracycline and gentamicin are the prominent contaminants in water and milk. In this study, the chitosan-ZnS and chitosan-ZnS-Au nanocomposites were fabricated using a laser ablation technique. The nanocomposites were covered on the glass substrate as a layer sensor characterized by analytical methods. Consequently, the thickness of layers was in the range of 36.3 to 38.21 nm. The surface plasmon resonance image patterns demonstrated the interaction of the gentamicin and oxytetracycline with nanocomposites. As a result, the sensor is sensitive to detect gentamicin, and the limit of detection, the affinity constant, and response time were about 0.1 ppm, 102.04 a.u., and 268 s respectively.

PhD Congratulations

Many Congratulations to Dr. Meisam Haghparast for achieving PHD degree! Many congratulations on your success. You’ve inspired all of us not only to dream but also to work hard to achieve them. Wish you many years of achievement of your goal and success.

Congratulations for our new paper in Journal of Magnetism and Magnetic Materials

Development of a novel four-channel atomic gradiometric magnetometer
for magnetocardiography: Advancing non-invasive cardiac research with
enhanced sensitivity and spatial resolution
M. Ranjbaran, R. Sedeyan, A. Zamani, M.M. Tehranchi, S.M.H. Khalkhali, S.
M. Hamidi

The field of magnetocardiography (MCG) has witnessed significant advancements with the use of atomic mag- netometers (AMs) and gradiometers, offering numerous advantages over traditional superconducting quantum interference devices (SQUIDs). This study focuses on the development of a highly sensitive four-channel atomic gradiometer specifically designed for measuring the biomagnetic fields of a rat’s heart. By utilizing gradiometric detection and monitoring deviations in the Larmor frequency of rubidium (Rb) atoms, this gradiometer captures cardiac signals with exceptional sensitivity and spatial resolution. One of the key challeng hies in utilizing AMs as gradiometers lies in minimizing cross-talk effects among the sensors to ensure accurate measurements. In this study, we successfully address this challenge, leading to precise and reliable data acquisition. Furthermore, our gradiometer demonstrates a linear response across a wide range of frequencies, enhancing its versatility and applicability in various experimental setups. The achieved sensitivity of 350 fT/√Hz by our atomic gradiometer showcases its potential in assessing MCG measurements for studying cardiac electrical activities. The non- invasive nature of the technique, combined with the elimination of cryogenic cooling requirements, opens up new avenues for cardiac research and diagnostics. The enhanced spatial and spatiotemporal resolution offered by optically pumped magnetometers (OPMs) further enhances our ability to understand and analyze complex cardiac phenomena.

News On Frequency Stabilization

In these days, the Journal of Photonics published a new paper entitled as “Simplified 1.5 μm Distributed Feedback Semiconductor Laser (DFB-LD) Frequency Stabilization System Based on Gas Absorption Chamber”

Abstract: The classical 1.5 μm band frequency-stabilized laser using acetylene gas saturated absorption can achieve high frequency stability and reproducibility, but its system design is complex and bulky. For some practical applications, a simple, compact system containing anti-interference abilities is preferred. In this study, a low-cost and simple-structured 1.5 μm frequency-stabilized laser is constructed using digital control methods, wavelength modulation technology, and acetylene gas absorption. The fiber input and output optical devices of the system significantly simplify the optical path and reduce the volume of the system. The error signal is obtained by the first-order differential method, and a combination of the high-speed comparator circuit and the microcontroller unit (MCU) is used to detect the error signal. Through the feedback control method of coarse temperature adjustment and fine current adjustment, the second-level frequency stability of the laser is stabilized within 100 kHz, that is, the frequency stability reaches 10−10. The designed system achieved continuous and stable operation for more than 6 h, and the long-term frequency stability reached 10−9.

News On Thermo-plasmonics

In these days, the Journal of Nano Letters published a new paper entitled as “Biological Applications of Thermoplasmonics”

ABSTRACT: Thermoplasmonics has emerged as an extraordinarily versatile tool with profound applications across various biological domains ranging from medical science to cell biology and biophysics. The key feature of nanoscale plasmonic heating involves remote activation of heating by applying laser irradiation to plasmonic nanostructures that are designed to optimally convert light into heat. This unique capability paves the way for a diverse array of applications, facilitating the exploration of critical biological processes such as cell differentiation, repair, signaling, and protein functionality, and the advancement of biosensing techniques. Of particular significance is the rapid heat cycling that can be achieved through thermoplasmonics, which has ushered in remarkable technical innovations such as accelerated amplification of DNA through quantitative reverse transcription polymerase chain reaction. Finally, medical applications of photothermal therapy have recently completed clinical trials with remarkable results in prostate cancer, which will inevitably lead to the implementation of photothermal therapy for a number of diseases in the future. Within this review, we offer a survey of the latest advancements in the burgeoning field of thermoplasmonics, with a keen emphasis on its transformative applications within the realm of biosciences.

فراخوان های پذیرش دانشجو بدون آزمون(استعداد درخشان)

ازمایشگاه مگنتوپلاسمونیک پژوهشکده لیزر و پلاسما دانشگاه شهید بهشتی تحت سرپرستی دکتر سیده مهری حمیدی در نظر دارد تعدادی دانشجو برای مقطع کارشناسی ارشد و دکتری از بین دانشجویان استعداد درخشان که علاقه مند به تحصیل در رشته فوتونیک هستند را جذب نماید.
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◀️فقط دانشجویان تحصیل کرده در رشته های زیر جایز به ارسال رزومه هستند :
فیزیک ، مهندسی اپتیک و لیزر ، برق ، الکترونیک

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ایمیل :M_hamidi@sbu.ac.ir
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