Advantages
1. Early and fast designs
2. Enabling Field upgrades
3. Creating product differentiation for suppliers
4. Creating flexible & adaptive products
5. Reducing power
6. Reducing manufacturing costs
7. Increasing bandwidths
Disadvantages
1. Inertia – Engineers slow to change
2. RCP designs requires comprehensive set of tools
3. 'Learning curve' for designers unfamiliar with reconfigurable logic
Applications
1. Wireless Base stations
2. Packetized voice(VOIP)
3. Digital Subscriber Line(DSL)
4. Software Defined Radio(SDR)
Chameleon chip (civil)
Quantum Dots
Quantum Dot fabrication techniques for QD diode lasers employ self-organized growth of uniform nanometer-scale islands of InGaAs on the surface of GaAs or InP. Under the proper choice of deposition conditions, a layer of material with a lattice constant different from that of the substrate may spontaneously transform to an array of three-dimensional islands. The size of these islands provides quantization in all three directions making them Quantum Dots.
Diode lasers based on InAs/GaAs Quantum Dots developed by Innolume and Zia Lasers (acquired by Innolume in December 2006) are uniquely positioned to serve silcon photonics as light sources in order to bring optical interconnect technologies to the mainstream computer applications.
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Three-dimensional nature of quantization of electrons and holes in these islands provides significantly improved temperature stability of laser output power basic characteristics. Fully temperature independent operation has been demonstrated eliminating the need of expensive control schemes.
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QD lasers demonstrate extremely low intensity noise, being an ideal CW source of light for high speed external modulation.
Owing to inhomogeneous broadening caused by size distribution of QDs, the effect of spectral hole burning can be controllably used to form very broad lasing spectrum (>80 nm) with uniform intensity distribution. These broad-band or “white” lasers can be used in WDM silicon photonics systems.
Another effect of broad gain spectrum of QD lasers is very stable mode-locking regime with high peak power, which has been unachievable. Mode-locked laser is a source of clocking in future silicon chips with high clocking frequency enabled by optical clock technology.
The emission range of InGaAs/GaAs QD lasers of 1.064 – 1.31 micrometer fits well the window of transparency of silicon based waveguides.
QD lasers arm Silicon Photonics to deliver cost efficient solutions for future Optical Interconnect and Optical Clock Systems.
Innolume has also developed a wide portfolio of laser
for specific wavelength range between 1.064 and 1.31 micron for medical, sensing and other applications.
Silicon Photonics
As computing and networking performance continue on their exponential growth track, defined by Moore’s Law, the exponentially increasing communication needs will soon exceed the limits of copper wiring. Communications links, or interconnects, are the biggest bottleneck in networks and computers. For example, the next generation of Ethernet runs at 10 Gb/s, and at this speed electrical signals in copper wires can only travel a small distance before fading out completely.
Optical fiber on the other hand is the ideal medium for communications over most distances. The fiber itself is very cheap, and light travels through it for miles even when launched with tiny amounts of power. Optical fiber also has the capability to carry data at rates up to one thousand times faster than 10Gb/s. At each end of the fiber, an optical transmitter/receiver (“transceiver”) is required to interface to the computer or switch. Unfortunately, these optical transceivers currently are extremely expensive. The typical cost of data communications today runs about $100/Gb/s. As a result, optical fiber communication has been largely confined to the capital-intensive long distance telecommunications infrastructure.
Fortunately, Silicon Photonics technology shows promises of delivering low cost seamless optical connectivity from hundreds of meter distances at the network level all the way down to millimeters distances for inter and intra-chip communication. The cost of Silicon Photonics is expected to reach well under $1/Gb/s, many times cheaper than typical data communication links.
Within 10 years, the established approach of using electricity in copper wiring just won’t work, and the ideal approach of using light in optical fiber is just simply too expensive. Only low cost disruptive technology can tip the balance from copper wiring to fiber optics to allow the computing and networking performance to continue on an exponential growth path. Silicon Photonics can fulfill this role.
Since silicon is not an efficient electrically pumped laser material, most silicon photonic solutions need a steady source, or Continuous Wave (CW), of laser light to power the interconnection. This source can be a typical laser based on III-V substrates such as GaAs and InP. The data transfer from electrical to optical occurs in a modulator, in which a voltage applied to a silicon photonic modulator will change the amount of light transmitted. Similarly, data on a light stream is converted back into an electrical current in a silicon photonic detector. Electronic drivers and receivers on each end of the path help with the signal quality. Finally, for increased total data rate and lower cost, it’s best to have many communication channels combined or wavelength division multiplexed (WDM), onto one fiber or waveguide. These modulator, detector and WDM elements can be integrated together on one Si photonic chip for best performance and lowest cost.
The cost of most silicon photonic devices can be relatively low, like that of silicon electronics. Therefore, the majority of the cost of silicon photonic interconnects will be in the source lasers that must meet tough specifications. These lasers will need to emit high power with low noise at wavelengths that are transparent in Silicon, above 1.1 micrometers. Also, for increased total bandwidth and cost efficiency, a preferred solution would send multiple data channels on multiple wavelengths on one fiber, called wavelength division multiplexing, or WDM. The laser also must operate in a very harsh environment, perhaps from below 0 C to over 100 C.
Innolume’s lasers based on are uniquely qualified to address these needs for silicon photonics.
Quantum cryptography becomes a reality [civil]
According to reliable sources from NEC, Commercial quantum cryptography, a revolutionary system that can produce quantum keys at a speed of 100Kbit/s and then broadcast it up to 40 kilometres along the commercial fibre optic lines will be available in the markets by the second half of 2005. Speaking in line with Kazuo Nakamura, senior manager of NEC's quantum information technology group at the company's Fundamental and Environmental Research Laboratories, it can be considered as a world record as it is a rare blend of speed and distance. As put by Akio Tajima, the assistant manager at the laboratory, this innovative concept has gone through several improvisations after it was successfully tested in April at the company’s laboratories in Tokyo. The system permits the users to swap the keys with a prior idea that they have not been disordered up during the transmission. The whole system works on the concept that the system works by implanting the encryption key on photons, which can be either in the receiver end or with an eavesdropper, as the photons cannot be cracked. Akio Tajima said that until last April the round-trip’ quantum cryptography method at NEC where it had a laser as well as a receiver at one end and also a mirror at the other end, faced some troubles regarding the high speed over long distances. Earlier the detector that turns the photons to electrons once they collide with it functioned very slowly. This created a problem in registering these photons, as there will be an avalanche of electrons with every collision. The team lead by Tajima has rectified that disadvantage now by developing a new detector that can work reliably at 100Kbit/s. This fast pace helps in clearing this whole bunch of electrons produced by the collision from the device, quickly so that they can register the next photon. The NEC scientists have also rectified the problem with the mirror used earlier in the system called the faraday mirror. The performance of this mirror, which can reflect the light in a 90-degree rotation from the input light, changes with temperature leading to quality loss. NEC today has improvised this concept of mirror, by producing a mirror that works efficiently with temperature variations. Another advantage of NEC system is that it has a conventional laser, which can transmit the photons through the fibre optic cables over a long distance with very less noise. Although there were powerful lasers that could trigger the propagation of photons over long distances, they all resulted in more noises leading to efficiency loss. According to Nakamura 'This is the world's fastest key generation technology at 40 kilometres'. He confirms his statement with various proofs. He said that the University of Geneva has achieved quantum transmission over a distance of over 60 kilometres, but at a much lower speed, while a system developed by Japan's National Institute of Advanced Industrial Science and Technology, a major government laboratory, has achieved nearly the same speed as NEC's system, but only at about half the distance. According to Toshiyuki Kanoh, chief manager of the company's System Platforms Research Laboratories, this break through system invented in collaboration with the Japan Science and Technology Agency's Exploratory Research for Advanced Technology and Japan's National Institute of Information and Communications Technology, will take an year to be launched in the commercial market as it’s software is still on the developing stage. He also added that they are going to create a commercial market for the system which it lacks now and is expecting the police, banks and financial institutions etc to be it’s clients by the mid of 2005. There is also a move to demonstrate this system in various exhibitions and seminars.
FLUORESCENT MULTILAYER DISC (FMD) [civil]
This ever-increasing capacity demand can only be only managed by the steady increase in the areal density of the magnetic and optical recording media. In future, this density increase is feasible only by taking advantage of the shorter wavelength lasers, higher lens numerical aperture (NA) or by employing near-field techniques. This increase is best achieved with optical memory technologies.
Fluorescent multiplayer disc (FMD) is a three dimensional storage that can store a large volume of data and is also capable of increasing the capacity of a given volume with an aim to achieve a cubic storage element having the dimensions of writing or reading laser wavelength. The current wavelength of 650 µm should be sufficient enough to store up to a Terabyte of data.
ZFS [civil]
Smart materials and Smart structures [civil]
A new generation of materials called smart materials is changing the way a structural system is going to be designed, built and monitored. Advances in composite materials, instrumentation and sensing technology (fiber-optic sensors) in combination with a new generation of actuator systems based on Piezoelectric ceramics and shape Memory Alloys have made this possible. Shape memory alloys have found applications in a variety of high performance products, ranging from aircraft hydraulic coupling and electrical connectors to surgical suture anchors. Since the material can generate high actuation forces in response to temperature changes, shape memory alloys have the potential to serve as an alternative to solenoids, special significance in the area of smart structures because it offers significant advantages over conventional actuations technologies in number of ways.