One method of cancer therapy is to utilize nano-antenna for thermal ablation.In this method,the electromagnetic waves emitted from the nano-antenna are absorbed by the tissue and lead to heating of cancer cells.If tem...One method of cancer therapy is to utilize nano-antenna for thermal ablation.In this method,the electromagnetic waves emitted from the nano-antenna are absorbed by the tissue and lead to heating of cancer cells.If temperature of cancer cells reaches a threshold,they will begin to die.For this purpose,an L-shaped frame nano-antenna(LSFNA) is designed to introduce into the biological tissue.Thus,the radiation characteristics of the LSFNA such as near and far-field intensities,directivity,and sensitivity to its gap width are studied to the optimization of the nano-antenna.The bio-heat and Maxwell equations are solved using the finite element method.To prevent damage to healthy tissues in this method,the antenna radiation must be completely controlled and performed carefully.Thus,penetration depth,special absorption rate,temperature distribution,and the fraction of tissue necrosis are analyzed in the biological tissue.That is why the design and optimization of the nano-antennas as a radiation source is important.Also,a pulsed source is used to excite the LSFNA.Furthermore,focusing and efficiency of the nano-antenna radiation on the cancer cell is tuned using an adjustable liquid crystal lens.The focus of this lens is changing under an electric field applied to its surrounding cathode.展开更多
A novel hybrid structure with high responsivity and efficiency is proposed based on an L-shaped frame nano-antenna(LSFNA)array for solar energy harvesting application.So,two types of LSFNAs are designed and optimized ...A novel hybrid structure with high responsivity and efficiency is proposed based on an L-shaped frame nano-antenna(LSFNA)array for solar energy harvesting application.So,two types of LSFNAs are designed and optimized to enhance the harvesting characteristics of traditional simple electric dipole nano-antenna(SEDNA).The LSFNA geometrical dimensions are optimized to have the best values for the required input impedance at three resonance wavelengths ofλ_(res)=10μm,15μm,and 20μm.Then the LSFNAs with three different sizes are modeled like a planar spiral-shaped array(PSSA).Also,a fractal bowtie nano-antenna is connected with the PSSA in the array gap.This proposed hybrid structure consists of two main elements:(I)Three different sizes of the LSFNAs with two different material types are designed based on the thin-film metal-insulator-metal diodes that are a proper method for infrared energy harvesting.(Ⅱ)The PSSA gap is designed based on the electron field emission proposed by the Fowler-Nordheim theory for the array rectification.Finally,the proposed device is analyzed.The results show that the PSSA not only has an averaged 3-time enhancement in the harvesting characteristics(such as return loss,harvesting efficiency,etc.)than the previously proposed structures but also is a multi-resonance wide-band device.Furthermore,the proposed antenna takes up less space in the electronic circuit and has an easy implementation process.展开更多
文摘One method of cancer therapy is to utilize nano-antenna for thermal ablation.In this method,the electromagnetic waves emitted from the nano-antenna are absorbed by the tissue and lead to heating of cancer cells.If temperature of cancer cells reaches a threshold,they will begin to die.For this purpose,an L-shaped frame nano-antenna(LSFNA) is designed to introduce into the biological tissue.Thus,the radiation characteristics of the LSFNA such as near and far-field intensities,directivity,and sensitivity to its gap width are studied to the optimization of the nano-antenna.The bio-heat and Maxwell equations are solved using the finite element method.To prevent damage to healthy tissues in this method,the antenna radiation must be completely controlled and performed carefully.Thus,penetration depth,special absorption rate,temperature distribution,and the fraction of tissue necrosis are analyzed in the biological tissue.That is why the design and optimization of the nano-antennas as a radiation source is important.Also,a pulsed source is used to excite the LSFNA.Furthermore,focusing and efficiency of the nano-antenna radiation on the cancer cell is tuned using an adjustable liquid crystal lens.The focus of this lens is changing under an electric field applied to its surrounding cathode.
文摘A novel hybrid structure with high responsivity and efficiency is proposed based on an L-shaped frame nano-antenna(LSFNA)array for solar energy harvesting application.So,two types of LSFNAs are designed and optimized to enhance the harvesting characteristics of traditional simple electric dipole nano-antenna(SEDNA).The LSFNA geometrical dimensions are optimized to have the best values for the required input impedance at three resonance wavelengths ofλ_(res)=10μm,15μm,and 20μm.Then the LSFNAs with three different sizes are modeled like a planar spiral-shaped array(PSSA).Also,a fractal bowtie nano-antenna is connected with the PSSA in the array gap.This proposed hybrid structure consists of two main elements:(I)Three different sizes of the LSFNAs with two different material types are designed based on the thin-film metal-insulator-metal diodes that are a proper method for infrared energy harvesting.(Ⅱ)The PSSA gap is designed based on the electron field emission proposed by the Fowler-Nordheim theory for the array rectification.Finally,the proposed device is analyzed.The results show that the PSSA not only has an averaged 3-time enhancement in the harvesting characteristics(such as return loss,harvesting efficiency,etc.)than the previously proposed structures but also is a multi-resonance wide-band device.Furthermore,the proposed antenna takes up less space in the electronic circuit and has an easy implementation process.
