Group 4: Pietro Quartero, Trent Terrence Steil, Annie Ly

=Yttrium Vanadate Optical Trap=


 * A tiny solid chip recently developed that is capable of capturing photons


 * An important step towards the next breakthrough in computing: lightning-fast optical computers.

=Background=

The fastest thing in the universe is light. This aspect of light makes it ideal for conveying information over long distances. A lot of the information flowing across the internet today already travels in the form of light through the use of optical fibers. However, when light reaches the end of the fiber, it must first be transformed into an electrical signal for processing. After, if the data is to be sent on is way again, it must then be converted back into light. This process therefore increases both costs and complexity for transferring data. Finding a way to eliminate the need for this conversion would increase speed and simplify the process. It would also help open doors for new forms of computing, such as those that involve quantum bits, or qubits. Development of all-optical networks and light-driven computers have not yet been achieved due to the face that the speed of light is non-negotiable. It is known that an electron's speed can be manipulated. It is possible to speed it up, slow it down or even make it stop completely. In contrast, the speed of a light particle, also known an as a photon, cannot be manipulated as easily. In order to create a memory however, it is required that things have to stay put which is why there exists the present need to transfer data from photons to electrons.

Origin


The creation of the yttrium vanadate optical trap is credited to Nicolas Gisin of the University of Geneva.  He and his colleagues' recent discovery may offer a new technology to escape the present complex process of transferring data from photons to electrons.  Dr Gisin and his team have built what they call a computer chip that is capable of holding on to photons for a microsecond.  Although this does not sound very long, unimpeded light can travel approximately 300 metres in that time. More significantly however, this microsecond is long enough to allow some useful computing to be done.

In essence, what Dr. Gisin has created is, an optical "echo-chamber" for a photon. It acts like a really tiny, really complex hall of mirrors bouncing the particle around. Although it does not actually slow light down, by keeping it bouncing around in a confined space, the particle is kept in the same spot for longer, which essentially achieves the same goal of stopping the photon completely.

=A Leap Forward in Computers?=

Optical Computers
Although still a ways away, the Yttrium Vanadate optical trap is a key breakthrough towards the development of optical computers. Presently photons can only be used as a means of transferring information from one computer to another. The ability to do so is not trivial, as the development of that technology and the laying of thousands of miles of fiber optic cables led to explosive growth in internet speed, telecommunications, the size and scope of the internet, and indirectly to globalization. However for processing of the information carried on fiber optic cables it still needs to be converted back into an electrical signal. This effectively reduces the efficiency of the data transfer. An optical computer, if developed, would eliminate the need for converting the data into an electrical signal- greatly increasing the speed and efficiency of computation. Added bonuses include that an optical computer would require less power to operate, and running such a machine would not give off heat, which would reduce efficiency as well. Furthermore, with data transferring at the speed of light within the computer the distances between the central processing unit an the memory become almost irrelevant.

Quantum Computers
The holy grail for computer scientists, and one of the main reasons behind the development of new technologies that use photons for processing, are Quantum Computers. These computers are still further away from development than simply optical computers, but are a far more exciting prospective technology. Quantum Computers are computers that make use of Quantum phenomena such as Superposition and Entanglement in processing data. The first phenomena has the potential to lead to massive time savings in computation, whereas the latter has the potential to lead to unbreakable computer security.

Theoretically, a Quantum Computer would use Qubits (or Quantum Bits) in processing. A normal bit is either a 0 or a 1, and it corresponds to either the presence or absence of an electrical signal. A Qubit is different, and far stranger. A Qubit can be either a 0 or a 1 or a Quantum Superposition of 0 and 1, meaning there are corresponding probabilities to each value, but actually still unknown. Using photons, and assigning their spin properties (either plus or minus) as the binary value of the bit, allows us to make use of Quantum Superposition. Putting a string of Qubits together gets us even larger Superpositions, effectively containing 2^n possible numbers, where n is the number of Qubits. For complex mathematical reasons associated with the probabilities of Quantum Superpositions, manipulating Qubits or strings of Qubits can lead to considerable time savings in computation. For example, if there were a hypothetical password to be broken, and was subject to the following conditions: In such an instance a normal computer would definitely have the correct answer in (n) x (time for each guess and check). If we assign n to be 1 billion, and say each iteration of a guess and check takes one second, our computer would definitely have an answer in 1 billion seconds, or roughly 31.7 years. With a Quantum Computer that utilizes Qubits however, such an operation can be completed by taking the square root of n, ad multiplying it by the time taken for each guess and check. The square root of one billion is approximately 31,623, meaning a quantum computer could complete this operation in just over 8 hours and 47 minutes! An astounding time saving!
 * 1) The password can be any number between 0 and n.
 * 2) The only way to find the password would be for a program to guess and check each possible answer.
 * 3) Each guess and check takes the same amount of time.
 * 4) There is no discernible pattern to be found from your wrong answers, meaning you might as well be submitting guesses at random.

Video: Elements of Physics: Quantum Mechanics

Quantum Computers, Continued


Another mysterious Quantum property that could theoretically be utilized with Quantum Computers is that of Qunatum Entanglement. It occurs when a proper description of something within a quantum state cannot be properly described without mentioning its counterpart too. Roughly speaking, if you do something to one particle, something will happen to its entangled counterpart too. This could have huge implications for encrypting messages, specifically with regards to interception and modification of messages. If two parties retain copies of an entangled key then any third party trying to gain knowledge about the key would be detected. Furthermore, any party trying to eavesdrop, or intercept messages that are in a quantum state must measure it in some way, which will induce detectable Quantum effects, again letting the other parties know of the presence of the eavesdropper.

=What Does This Mean?=

Advantages

 * 1) The Yttrium Vanadate optical trap is a solid rather than a gas.  All other optical traps have been gases.  The problem with using gas is that it is hard to control.  Magnetic fields are required in order to keep the gas in a fixed place.  The solid Yttrium Vanadate trap however does not require magnetic fields and can easily be carried in a compact solid state.
 * 2) This particular trap also works at 3 degrees above Kelvin.  Other optical trap designs have been required to reach a temperature of a few thousandths of a degree above absolute zero.  Because reaching 3 degrees above Kelvin was accomplished nearly a century ago, it makes it easier for scientists to accomplish.
 * 3) Optical computers in general are significantly faster and more efficient meaning they are able to undertake extremely complex computations (highers performance)
 * 4) Optical computers will require less energy than conventional computers.  The use of photons rather than electrons means less internal friction will exist, cutting the energy that will be required to operate the computer
 * 5) As a result of less friction, less heat will be released as well.  Lasers are typically used in optical computers so there is little heat given off.  Conventional computers however use electrons that bounce off each other and this produces heat.

Disadvantages

 * 1) The Yttrium Vanadate optical trap can only work at 3 degrees above Kelvin.  This means that people cannot expect to own one in their homes for personal use.
 * 2) The cost of these machines will be extremely expensive.  Governments may be the only people that will be able to utilize this particular technology in the near future.
 * 3) Creating an effective optical trap means that the manufacturing must be exact in order for the device to work properly.  A lack of precision in manufacture is a significant disadvantage that researchers are trying to fix.
 * 4) The need for expensive high tech factories will increase in order for production of this technology to grow.
 * 5) Incompatibility with today's software.  Conventional computers that are in use today are designed with the Von Neumman architecture.  Optical computers will be designed utilizing different architecture thus conventional software will not be able to utilize the speed of the optical computers.
 * 6) Research is still in it's infancy meaning that optical and quantum computers may not be a reality for years to come.

Applications



 * Due to the extremely fast speed that photons travel at, optical and quantum computers will be able to crack passwords in seconds rather than months or years.
 * Opposite of cracking passwords, governments would be able to use encryption that will be nearly impossible to decrypt.
 * These capabilities could revolutionize government security, however if this technology got into the hands of the wrong people it could be catastrophic in terms of security as well.
 * Can be used for computational problems that could take years for a conventional computer to analyze. For example, the LHC Tunnel in Switzerland is a large mass particle accelerator which is attempting to uncover the matter of the Universe.  The information collected from this experiment will be more information than everything on Earth today.  With an optical computer, the information will be able to be managed and analyzed much quicker than a regular supercomputer.  Without optical computers, this information is nearly impossible to conquer through the course of a lifetime.
 * Nearly every academic research area will benefit due to the speed and efficiency that the computers will be able to do computations and manage information.
 * Physics, Chemistry, Engineering, Architecture, Medicine, Biology, Business, etc.

=Conclusion=



The Yttrium Vanadate Optical Trap will be extremely beneficial in assisting with the breakthrough of fully functional optical and quantum computers. There are a number of disadvantages with the production of the technology, however the potential advantages this new technology will provide by far outweighs the disadvantages. Due to the fact that optical and quantum computers will completely revolutionize computer life, money for research should continue to be provided. Although this breakthrough may be years in the future, continuing research will no doubt allow for such a revolution to take place.

=References=


 * http://130.75.63.115/upload/lv/wisem0708/SeminarIT-Trends/html/tr/right/5.%20Advantages%20and%20Disadvantages%20of%20Optical%20Computers.htm


 * http://www.economist.com/science/tq/displaystory.cfm?story_id=13174421


 * http://en.wikipedia.org/wiki/Large_Hadron_Collider


 * http://computer.howstuffworks.com/quantum-computer.htm


 * http://www.tongue-twister.net/mr/physics/index.htm


 * http://www.wiziq.com/tutorial/16010-Quantum-Computer-II


 * http://en.wikipedia.org/wiki/Quantum_computation


 * http://en.wikipedia.org/wiki/Quantum_superposition


 * http://en.wikipedia.org/wiki/Quantum_entanglement


 * http://en.wikipedia.org/wiki/Quantum_cryptography


 * http://www.nature.com/news/2008/080722/full/news.2008.967.html