Ultrasonic measurement is an important technique that is used in various fields of science and technology, including physical property evaluation, imaging and sensing. I use a measurement technique that uses light to excite and detect ultrasonic waves in the frequency range of GHz to THz, and I use this to evaluate the mechanical and acoustic properties of microstructures and thin films with sizes in the nano to micro range, as well as for non-destructive testing.

Conventional ultrasound had a wavelength of several micrometres or more, so it was impossible to measure at the nanoscale.
However, by using femtosecond pulse lasers to manipulate ultrasound with a wavelength of the order of 10 nm, I have achieved the evaluation of the mechanical properties of nano-materials and non-destructive testing in the nano-region.

• Development of unique measurement technology that makes full use of light and sound (lasers and ultrasound)
• Excitation and detection of vibration phenomena in nano-materials and GHz bands
• Accurate measurement of sound velocity and elastic constants under high magnetic fields of 10 to 600 K and up to 5 T
• Measurement of magnetic damping constants and saturation magnetisation from magnetisation oscillations in the time domain
• Main targets include nano-thin films of metals, piezoelectric materials, and magnetic materials, as well as superhard materials such as diamond and tungsten carbide
• Contributing to the development of materials and the elucidation of the characteristics of filters for wireless communication in smartphones
• Applications include the development of highly sensitive biosensors using ultrasound, which has a shorter wavelength than light, and monitoring the breaking process of nanowires

This measurement method enables the inspection of defects in semiconductors on the order of nm, and the evaluation of the characteristics of acoustic filters, which are essential for 5G communication devices.

• One of our major research focuses is to design the novel drug nanoparticles, so called “Nano-prodrugs”, and to apply them as anticancer drugs or eye drops with excellent delivery efficiency. Nano-prodrugs are constructed by synthetic prodrugs molecules which contains poorly water-soluble substituent. They could be fabricated to nanoparticles with 100 nm or less in size by our reprecipitation technique, which has been used to create organic nanomaterials. We are aiming at practical application of our Nano-prodrugs in the near future.

Our reprecipitation technique for fabricating organic nanomaterials is a versatile technique that can be applied to various organic molecules as well as drug compounds. We hope to conduct collaborative research with a willing company on controlling and evaluating properties of the organic nanoparticles.

Ultrasonic measurement is an important technique that is used in various fields of science and technology, including physical property evaluation, imaging and sensing. I use a measurement technique that uses light to excite and detect ultrasonic waves in the frequency range of GHz to THz, and I use this to evaluate the mechanical and acoustic properties of microstructures and thin films with sizes in the nano to micro range, as well as for non-destructive testing.

Conventional ultrasound had a wavelength of several micrometres or more, so it was impossible to measure at the nanoscale.
However, by using femtosecond pulse lasers to manipulate ultrasound with a wavelength of the order of 10 nm, I have achieved the evaluation of the mechanical properties of nano-materials and non-destructive testing in the nano-region.

• Development of unique measurement technology that makes full use of light and sound (lasers and ultrasound)
• Excitation and detection of vibration phenomena in nano-materials and GHz bands
• Accurate measurement of sound velocity and elastic constants under high magnetic fields of 10 to 600 K and up to 5 T
• Measurement of magnetic damping constants and saturation magnetisation from magnetisation oscillations in the time domain
• Main targets include nano-thin films of metals, piezoelectric materials, and magnetic materials, as well as superhard materials such as diamond and tungsten carbide
• Contributing to the development of materials and the elucidation of the characteristics of filters for wireless communication in smartphones
• Applications include the development of highly sensitive biosensors using ultrasound, which has a shorter wavelength than light, and monitoring the breaking process of nanowires

This measurement method enables the inspection of defects in semiconductors on the order of nm, and the evaluation of the characteristics of acoustic filters, which are essential for 5G communication devices.

The sea pineapple is the only animal that produces cellulose, and its shells, excluding the edible parts, are treated as industrial waste. By removing proteins and other components from the sea squirt shells and fibrillating them, cellulose nanofibers (CNFs) can be extracted. We have focused on the fact that CNFs derived from sea squirt shells have a higher degree of crystallinity and greater mechanical strength compared to those from wood, and we are exploring various applications of this material. Furthermore, since the material transforms into high-quality carbon upon calcination, we successfully developed "nano-blood carbon catalysts" by mixing it with dried blood powder and calcining the mixture. These catalysts are being applied in fuel cells, water electrolysis, and metal-air batteries.

CNFs derived from sea pineapple's shells have a higher degree of crystallinity compared to those from wood and provide longer fibers, resulting in high strength. When calcined, they transform into high-performance carbon.

• We are the only research laboratory that has consistently developed a process for the simple and large-scale purification of CNFs derived from sea pineapple's shells, along with the creation of film materials that leverage their unique properties (mechanical, engineering, surface science, electrical, and thermal characteristics), as well as the development of carbonized materials.

We offer materials derived from sea pineapples' shell CNFs, as well as their carbonized products and catalysts. Please feel free to consult us regarding material supply, carbonization processes, or the utilization of catalysts.

• One of our major research focuses is to design the novel drug nanoparticles, so called “Nano-prodrugs”, and to apply them as anticancer drugs or eye drops with excellent delivery efficiency. Nano-prodrugs are constructed by synthetic prodrugs molecules which contains poorly water-soluble substituent. They could be fabricated to nanoparticles with 100 nm or less in size by our reprecipitation technique, which has been used to create organic nanomaterials. We are aiming at practical application of our Nano-prodrugs in the near future.

Our reprecipitation technique for fabricating organic nanomaterials is a versatile technique that can be applied to various organic molecules as well as drug compounds. We hope to conduct collaborative research with a willing company on controlling and evaluating properties of the organic nanoparticles.

• Our research aims at developing methods, including instrumentation, for characterizing surface (or interface) at the nano-meter level. Most of our research subjects are related to the surface forces measurement, which can directly monitor the interaction between two surfaces. We study phenomena occurring at the solid-liquid interface such as adsorption and structuring of liquids. We have developed the resonance shear measurement which is a sensitive method for evaluating properties of confined liquid for nano-rheology and tribology. Twin-path surface forces apparatus we developed enabled us to study wide variety of samples such as metals, ceramics and plastics.

These methods are applicable for characterizing lubricants, nano-materials, paints, sealants, and cosmetics. We hope to conduct collaborative research with a willing company for a practical application of this technology in industry.

• Our research aims at developing methods, including instrumentation, for characterizing surface (or interface) at the nano-meter level. Most of our research subjects are related to the surface forces measurement, which can directly monitor the interaction between two surfaces. We study phenomena occurring at the solid-liquid interface such as adsorption and structuring of liquids. We have developed the resonance shear measurement which is a sensitive method for evaluating properties of confined liquid for nano-rheology and tribology. Twin-path surface forces apparatus we developed enabled us to study wide variety of samples such as metals, ceramics and plastics.

These methods are applicable for characterizing lubricants, nano-materials, paints, sealants, and cosmetics. We hope to conduct collaborative research with a willing company for a practical application of this technology in industry.

• 1) We investigate interesting properties of nanostructures and develop materials and devices utilizing nanostructures.
• 2) We have techniques and skills on low-noise electric measurements, cryogenics, nanofabrication, and data informatics. We are open to new collaborations.

The sea pineapple is the only animal that produces cellulose, and its shells, excluding the edible parts, are treated as industrial waste. By removing proteins and other components from the sea squirt shells and fibrillating them, cellulose nanofibers (CNFs) can be extracted. We have focused on the fact that CNFs derived from sea squirt shells have a higher degree of crystallinity and greater mechanical strength compared to those from wood, and we are exploring various applications of this material. Furthermore, since the material transforms into high-quality carbon upon calcination, we successfully developed "nano-blood carbon catalysts" by mixing it with dried blood powder and calcining the mixture. These catalysts are being applied in fuel cells, water electrolysis, and metal-air batteries.

CNFs derived from sea pineapple's shells have a higher degree of crystallinity compared to those from wood and provide longer fibers, resulting in high strength. When calcined, they transform into high-performance carbon.

• We are the only research laboratory that has consistently developed a process for the simple and large-scale purification of CNFs derived from sea pineapple's shells, along with the creation of film materials that leverage their unique properties (mechanical, engineering, surface science, electrical, and thermal characteristics), as well as the development of carbonized materials.

We offer materials derived from sea pineapples' shell CNFs, as well as their carbonized products and catalysts. Please feel free to consult us regarding material supply, carbonization processes, or the utilization of catalysts.

• In our laboratory, miniature and highly-functional photonic devices based on new optical phenomena caused by the interaction of ultrafine microstructures with light have been studied. In addition, development of new production technology to overcome the problems that have been obvious from the practical application viewpoint of nanophotonic devices has been performed.
• • -Main research topics--
  MEMS tunable metamaterials for optical control.
• Structural color filters using subwavelength gratings for the applications of display and spectroscopic analyzers.
• Surface-smoothing technology using surface self-diffusion.
• Study of low loss silicon nanophotonic devices.

We aim to realize optical filters, optical resonators, and color filters, by using above technologies. Also, development of nano-photonic elements fabricated by a nanoimprint technology has been progressed.
We hope to conduct collaborative research with a willing company for a practical application of this technology in industry.

Light curing high strength resin mold
https://www.t-technoarch.co.jp/data/anken_en/T11-053.pdf

• Nakagawa group has dedicated to pursue scientific principles for molecular control of interface function occurring at polymer/other material interfaces and to put them into practice in nanoimprint lithography promising as a next generation nanofabrication tool. We are developing advanced photo-functional materials such as sticking molecular layers for "fix by light", UV-curable resins and antisticking molecular layers for "preparation by light", fluorescent resist materials for "inspection by light", and hybrid optical materials "available to light" and new research tools such as mechanical measurement systems to evaluate release property of UV-curable resins.

Our research aims at creating new devices to control photon, electron, and magnetism.

• Monoatomic layered materials of Graphene, Transition metal sulfide nanosheet, nanocrystalline active materials, nanoparticles and nanoporous materials are investigated for realizing high capacity, high power, high safety and low cost energy storage devices as a post- Lithium ion battery. Advanced chemistry of functional materials and device processes for All solid state battery, Magnesium battery, fuel cells, supercapacitor and wearable batteries are investigated.

Academia – Industry collaboration with manufacturing companies of functional materials, batteries, and also smart grid, renewable energy, electrical power companies are encouraged for developments of advanced energy materials and post-Lithium ion battery.

• Hybrid materials that show multi-functions of polymer and nanoparticles are expected to be used in future industries, and thus many research and development have been actively conducted. However, since the affinity of polymer and inorganic nanoparticles is very low, in most of the cases, properties of different materials are incompatible in the hybrid materials. To create the hybrid materials with incompatible multi-functions has been considered a difficult task.
• However, by using supercritical fluid technology, we have succeeded in making hybrid materials with incompatible multi-functions.

Now, variety of hybrid materials are being developed, including
・Transparent, flexible, high reflective index, and high fabricability,
・Flexible, high heat conductivity, low electric resistivity, and high fabricability.

• We invented supercritical hydrothermal synthesis method for the synthesis of organic modified nanoparticles (NPs). Under the supercritical state, the organic molecules and metal salt aqueous solutions are miscible and water molecule works as an acid/base catalyst for the reactions. Organic-inorganic conjugate NPs can be synthesized under this condition. This hybrid NPs show high affinity with the organic solvent or the polymer matrix, which leads to fabricate the organic inorganic hybrid nanomaterials with the trade-off function (super hybird nanomaterials). These hybrid materials of polymer and ceramics fabricated with NPs achieve both high thermal conductivity and easy thin film flexible fabrication, namely trade-off function.

For example, by the surface modification of BN particles by supercritical method, affinity of BN and polymers could be improved, so that high BN content of hybrid materials, thus high thermal conductivity materials, could be synthesized. Also by dispersing high refractive index NPs like TiO2 or ZrO2 into polymers transparently, we can tune the refractive index of the polymers. CeO2 nanoparticles are expected to be used for high performance catalysts. To transfer those supercritical fluid nano technologies, a consortium was launched with more than 70 companies.

• Since we have developed the techniques (ion control plasma) to generate and control ions, electrons, reactive species (radicals) in the low temperature non-equilibrium plasmas which I can touch by hand, the composite materials using nanoparticles, nanocarbons, biological molecules are synthesized in the nano-electronics field, the minimally-invasive and highly-efficient drug/gene transfection systems are developed in the medical field, and bacteria and insects are killed by the plasma in place of pesticide in the agricultural field.

The ion-controlled plasmas are applied for the minimally-invasive gene transfection system, next-generation agricultural system, the electrode material of highly-efficient battery, and so on. We hope to conduct the collaborative research with a willing company for a practical application of the novel plasma nano-medical-agricultural applied technology in industry.

• In our laboratory, miniature and highly-functional photonic devices based on new optical phenomena caused by the interaction of ultrafine microstructures with light have been studied. In addition, development of new production technology to overcome the problems that have been obvious from the practical application viewpoint of nanophotonic devices has been performed.
• • -Main research topics--
  MEMS tunable metamaterials for optical control.
• Structural color filters using subwavelength gratings for the applications of display and spectroscopic analyzers.
• Surface-smoothing technology using surface self-diffusion.
• Study of low loss silicon nanophotonic devices.

We aim to realize optical filters, optical resonators, and color filters, by using above technologies. Also, development of nano-photonic elements fabricated by a nanoimprint technology has been progressed.
We hope to conduct collaborative research with a willing company for a practical application of this technology in industry.

• Nanoporous metals have drawn considerable attention due to their highly functional properties. They are generally produced by selective dissolution of elements from a multicomponent alloy (known as the dealloying method). As this method is based on differences in the electrode potential of each element present in the alloy, and this potential is high for noble metals, porous structure can be obtained only for noble metals. Recently we have found a new, simple and easy dealloying method without using aqueous solution, which enable us to develop an open nanoporous non-oxidized metallic material even with base metals (such as Ti, Ni, Cr, Fe, Mo, etc), metalloids and their alloys.

This technique is very powerful for developing new functional electrodes, catalysts, filters as well for removing toxic metallic element from the surface of biomaterials containing the toxic element.