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Congratulations for our new paper

Many Congratulations for our new paper in Journal of scientific reports:

Quasi‑BIC based all‑dielectric metasurfaces for ultra‑sensitive
refractive index and temperature sensing

Seyedeh Bita Saadatmand, VahidAhmadi1* & Seyedeh Mehri hamidi

Abstract- In this paper, an all-dielectric metasurface that measures refractive index and temperature using silicon disks is presented. It can simultaneously produce three resonances excited by a magnetic toroidal dipole, magnetic toroidal quadrupole, and electric toroidal dipole, in the THz region. Asymmetric structures are used to generate two quasi-bound states in the continuum (BIC) resonances with ultra-high-quality factors driven by magnetic and electric toroidal dipoles. We numerically study and show the dominant electromagnetic excitations in the three resonances through near-field analysis and cartesian multipole decomposition. The effects of geometric parameters, scaling properties, polarization angles, incident angles, and silicon losses are also investigated. The proposed metasurface is an excellent candidate for sensing due to the extremely high-quality factor of the quasi-BICs. The results demonstrate that the sensitivities for liquid and gas detection are S_l = 569.1 GHz/RIU and S_g = 529 GHz/RIU for magnetic toroidal dipole, and S_l = 532 GHz/RIU and S_g = 498.3 GHz/RIU for electric toroidal dipole, respectively. Furthermore, the sensitivity for temperature monitoring can reach up to 20.24 nm/°C. This work presents a valuable reference for developing applications in the THz region such as optical modulators, multi-channel biochemical sensing, and optical switches.

News On Biosensors

The Journal of Materials Research Express published a paper entitled as “Excitation of Bloch surface wave using silver nanoparticles for sensitivity enhanced biosensor”

A silver nanoparticles array is introduced on the top layer of all-porous-silicon refractive index sensor. Bloch surface wave (BSW) resonance is realized at the interface between air and multilayer porous silicon structure, which can be excited by different coupling schemes: the Kretschmann prism and silver nanoparticles array. In addition to sustaining the BSW mode, the silver nanoparticles add an additional degree of freedom to the phase-matching conditions. We demonstrated the sharp BSW reflectivity dip with an ultra-narrow linewidth. The performance of the designed BSW sensor is numerically calculated by the rigorous coupled wave analysis (RCWA) method under s-polarized light. The optimized silver nanoparticles coupled BSW (AgNPs-BSW) sensor has a much higher figure of merit (~17000RIU-1) than conventional prism-coupled BSW sensors. The azimuthal sensitivity can reach about 703°/RIU or even higher. The proposed silver nanoparticles coupled BSW(AgNPs-BSW) sensor exhibits the capacity to eliminate the adverse effects of inhomogeneous penetration of analytes. With such excellent performance, our study demonstrates its potential applications in the field of chemical and biological sensors in the future.

Our Group Meeting

Our Group Meeting _ Tuesday 14 Nov 2023

Congratulations for PHD Defense

Many Congratulations to Dr. Hayder Maki Hamodi 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.

News

رونمایی از حسگر تمام اتوماتیک پلاسمونی ساخت شرکت حسگرسازان نور گستر (پلاسنس) به مدیریت خانم دکتر حمیدی توسط معاون علمی ریاست جمهوری

روح الله دهقانی فیروزآبادی، معاون علمی، فناوری و اقتصاد دانش‌بنیان رئیس‌جمهور؛ پیش از ظهر دوشنبه (۱۵ آبان ۱۴۰۲) ازچهاردهمین نمایشگاه بین المللی نانو بازدید و از جدیدترین محصولات فناورانه نانویی رونمایی کردند. در میان محصولات فناورانه، حسگر تمام اتوماتیک پلاسمونی ساخت شرکت دانش بنیان حسگرسازان نور گستر از پژوهشکده لیزر وپلاسمای دانشگاه شهید بهشتی و به مدیریت خانم دکتر سیده مهری مهری حمیدی سنگدهی توسط معاون علمی ریاست جمهوری رونمایی شد

خانم دکتر حمیدی سنگدهی مدیرعامل شرکت دانش بنیان پلاسنس از دانشگاه بهشتی، خاطرنشان کردند که حسگر تمام اتوماتیک پلاسمونی برای اولین بار در ایران تولید شده است و قیمت آن در مقایسه با نمونه مشابه خارجی آن به مراتب پایین تر است و در واقع یک چیدمان اپتیکی آزمایشگاهی بصورت دستگاه جمع شده است که در صنایع مختلف مانند صنایع غذایی، دارویی و حوزه های زیست پزشکی برای کاربردهای حسگری مورد استفاده قرار میگیرد

Congratulations 🎉

حضور پررنگ شرکت حسگرسازان نور گستر (پلاسنس) در نمایشگاه بین المللی ستاد توسعه فناوری‌های اپتیک و کوانتوم

چهاردهمین نمایشگاه فناوری نانو امسال (13 تا 16 آبان ماه 1402) در حالی برگزار شد که بخش‌های بسیاری برای بازدید بازدیدکنندگان به آن اضافه شده بود. غرفه محصولات دارای نوآوری جهانی، غرفه ستاد اپتیک و کوانتوم، غرفه شرکت‌های فعال در زمینه کوانتوم از جمله بخش‌های اضافه شده به چهاردهمین دوره نمایشگاه فناوری نانو بوده است

دبیر ستاد توسعه فناوری های اپتیک و کوانتوم با بیان اینکه این برای اولین‌بار است که شرکت‌های حوزه اپتیک و لیزر در نمایشگاه نانو حضور دارند، ادامه داد: در سال‌های گذشته دستاوردهای شرکت‌های ‌این حوزه در نمایشگاهی تحت عنوان اپتیک و لیزر عرضه می‌شدند، ولی فعالان این عرصه با تاکید بر فناوری‌های فوتونیک و لیزر و اپتیک همراه با فناوری‌های مبتنی بر کوانتوم که در حال حاضر اشتراکات زیادی با فناوری‌های نوری یا اپتیکی دارند، در این نمایشگاه حضور یافته‌اند

در این میان، شرکت دانش بنیان حسگرساران نور گستر به مدیریت سرکار خانم دکتر مهری حمیدی از پژوهشکده لیزر و پلاسمای دانشگاه شهید بهشتی حضور داشت و به معرفی محصولات فناورانه خود در حوزه اپتیک و کوانتوم پرداخت. محصولات این شرکت دانش بنیان شامل دستگاه حسگری تمام اتوماتیک پلاسمونی، سل های اتمی و سامانه تصویربرداری پلاسمونی بود که برای اولین بار در کشور تولید شده اند. سومین روز برگزاری نمایشگاه دکتر روح الله دهقانی فیروزآبادی ضمن بازدید از نمایشگاه بین المللی ستاد اپتیک و کوانتوم از دستگاه حسگر پلاسمونی تمام اتوماتیک ساخت شرکت پلاسنس از دانشگاه شهید بهشتی رونمایی کردند

Congratulations for our new Paper

Congratulations for Our New Paper in Journal of Theoretical and Applied Physics:

Spatial self-phase modulation in plasmon excited Graphene/WS₂ heterostructure

Hayder Maki Hamodi, Raad Sami Fyath, Seyedeh Mehri Hamidi

Abstract: In this work a spatial phase modulation and four-wave mixing in Graphene/ tungsten disulfide (WS₂) heterostructure have been demonstrated, which is excited by plasmons of nano-plasmonic donate shape rings. For this purpose, a laser writing system was used to fabricate nanohole arrays and cover them with the plasmonic gold thin film via a sputtering machine and WS₂ and Graphene heterostructure by chemical vapor deposition method. After evaluating the plasmon excitation in this system by the ellipsometric method, the probe laser excitation was set to 980 nm to record spatial phase modulation, and also, four-wave mixing was used. Our results show spatial self-phase modulation (SSPM) and temperature enhancement due to the nonlinear enhancement of two-dimensional structure by heterostructure substances suitable for new-generation optical devices.

Congratulations for our new paper

Many Congratulations for our new paper in Journal of Optical Material Express:

Light blocking and phase modulation based on Thermo-Plasmonic hotspots in WS₂ monolayer

Hayder Maki Hamodi, Raad Sami Fyath, Seyedeh Mehri Hamidi

Here we demonstrate light blocking and phase modulation in nano-plasmonic donate shape rings based on the thermo-plasmonic effect in these structures. For this purpose, we use a laser writing system to fabricate nanohole arrays and cover them with plasmonic gold thin film via a sputtering machine. The chemical vapor deposition method is also used to produce WS₂ layer which is suitable for light blocking and phase modulation due to, nonlinearity of this two-dimensional material. After theoretically and experimentally evaluating the plasmonic donate shaped substrate, we use ellipsometric method to characterize the optical modes of the samples and record the switching manner and light blocking phenomena under the probe laser excitation set to 980 nm. Our results show phase modulation based on thermo-plasmonic effect of nano gap in donated double rings and light blocking by thermal expansion of the WS₂ layer which can open new insight in plasmon and two-dimensional material-based devices.

News On Nanomaterials

In these days, the Journal of RSC advances published a new paper entitled as “Organic and inorganic nanomaterials: fabrication, properties and applications”

Nanomaterials and nanoparticles are a burgeoning field of research and a rapidly expanding technology sector in a wide variety of application domains. Nanomaterials have made exponential progress due to their numerous uses in a variety of fields, particularly the advancement of engineering technology. Nanoparticles are divided into various groups based on the size, shape, and structural morphology of their bodies. The 21st century’s defining feature of nanoparticles is their application in the design and production of semiconductor devices made of metals, metal oxides, carbon allotropes, and chalcogenides. For the researchers, these materials then opened a new door to a variety of applications, including energy storage, catalysis, and biosensors, as well as devices for conversion and medicinal uses. For chemical and thermal applications, ZnO is one of the most stable n-type semiconducting materials available. It is utilized in a wide range of products, from luminous materials to batteries, supercapacitors, solar cells to biomedical photocatalysis sensors, and it may be found in a number of forms, including pellets, nanoparticles, bulk crystals, and thin films. The distinctive physiochemical characteristics of semiconducting metal oxides are particularly responsible for this. ZnO nanostructures differ depending on the synthesis conditions, growth method, growth process, and substrate type. A number of distinct growth strategies for ZnO nanostructures, including chemical, physical, and biological methods, have been recorded. These nanostructures may be synthesized very simply at very low temperatures. This review focuses on and summarizes recent achievements in fabricating semiconductor devices based on nanostructured materials as 2D materials as well as rapidly developing hybrid structures. Apart from this, challenges and promising prospects in this research field are also discussed.

Congratulations for PHD degree

Many Congratulations to Dr. Majid Haddawi 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.