Electrochemistry to Benefit Photonics: Nanotubes Can Control Laser Pulses
October 15, 2019 | SkoltechEstimated reading time: 2 minutes
Optical phenomena that we encounter in our everyday life, such as reflection, refraction or absorption of light, do not depend on the intensity of incident light. However, at very high radiation intensities, a new class of phenomena arises, that causes changes in the refraction index, self-focusing of light or emergence of radiation at new wavelengths. These and other phenomena that are dependent on the intensity of light are studied by a section of physics called nonlinear optics. Normally, the efficiency of nonlinear optical response is material’s invariable characteristic determined by its structure.
Using nanomaterials as an optical nonlinear medium opens up new perspectives for nonlinearity control thanks to the fact that the majority of its atoms are exposed to the surface. This enables controlling a material’s electronic structure and thus changing its nonlinear optical response.
Skoltech scientists in collaboration with their colleagues from the Fiber Optics Research Center of RAS, Novosibirsk State University and the University of Warwick (UK) have proposed a method for controlling the saturable absorption of carbon nanotubes using electrochemical gating. Saturable absorption is a nonlinear optical effect when the absorption coefficient decreases with increasing power of incident light. Thus, the material gets more transparent under intense laser radiation. “We showed that magnitude of the nonlinear transparency can be controlled by placing the material in an electrochemical cell. It has been known that, if placed in the electrochemical cell, nanotubes can accumulate a considerable amount of electrical charge on their surface. What has not been known thus far is that the charge accumulation leads to a significant change in the material’s nonlinear optical response and, in particular, a reduction in saturable absorption,” says the first author of the study and Senior Research Scientist at Skoltech, Yuriy Gladush.
Also, the authors have looked into one of the potential practical applications of a material with a controlled nonlinear response. Saturable absorption is widely used in laser systems to generate femtosecond light pulses. All you have to do is place a saturable absorber with given parameters in the laser cavity. “We assumed that the laser generation regime can be controlled by adjusting the material’s nonlinear response. To do so, we built an electrochemical cell with carbon nanotubes placed on the optical fiber surface and integrated it into the fiber optic laser cavity. We discovered that by applying voltage to the device, one can switch from continuous laser generation regime to pulsed regime in the femtosecond and microsecond ranges. This invention paves the way for universal laser systems with a controllable pulse duration that can be used in laser processing of materials, laser surgery, and aesthetic medicine,” explains Albert Nasibulin, Head of Skoltech’s Laboratory of Nanomaterials and Professor of RAS.
Suggested Items
Indium Corporation Expert to Present on Pb-Free Solder for Die-Attach in Discrete Power Applications
04/30/2024 | Indium CorporationIndium Corporation Product Manager – Semiconductor Dean Payne will present at the Advanced Packaging for Power Electronics conference, hosted by IMAPS, held May 8-9 in Woburn, Massachusetts, USA.
Real Time with... IPC APEX EXPO 2024: Adhesive Materials and Equipment Update with Dymax
05/01/2024 | Real Time with...IPC APEX EXPOVirginia Hogan, global business development manager at Dymax, discusses adhesive materials, dispensing and curing equipment, a new, high-reliability conformal coating, and various materials and dispensing methods.
Real Time with... IPC APEX EXPO 2024: Sustainability in the Industry
04/26/2024 | Real Time with...IPC APEX EXPOGuest Editor Henry Crandall and Chris Nash of Indium Corporation discuss the company's 90th anniversary and its focus on sustainability. They focus on the benefits of sustainable materials, their compatibility, and value propositions. The conversation also highlights how Durafuse LT technology's role in reducing reflow temperatures is leading to significant cost and energy savings. Nash also touches on downstream sustainability efforts such as using recycled materials for packaging.
SMC Korea 2024 to Highlight Semiconductor Materials Trends and Innovations on Industry’s Path to $1 Trillion
04/24/2024 | SEMIWith Korea a major consumer of semiconductor materials and advanced materials a key driver of innovation on the industry’s path to $1 trillion, industry leaders and experts will gather at SMC (Strategic Materials Conference) Korea 2024 on May 29 at the Suwon Convention Center in Gyeonggi-do, South Korea to provide insights into the latest materials developments and trends. Registration is open.
Groundbreaking Ceremony Marks the Beginning of a New Era for Newccess Industrial; The Construction of the MINGXIN Building
04/12/2024 | Newccess IndustrialOn a clear and sunny day in March, the groundbreaking ceremony for the MINGXIN Building took place in Shenzhen, China. This moment marked the official commencement of construction for a project that will reshape the semiconductor materials industry.