Quantum computing now a reality

Last night's "random walk" on the Internet awarded me with some shock and awe. While looking for something else on the NASA website, I discovered about the quantum computing project at NASA's QuAIL, where they are installing a "512-qubit D-Wave Two quantum computer".
Intrigued, a further Google search on "D-Wave quantum computer" brought me to these:

D-Wave's Quantum Computer Courts Controversy
http://www.scientificamerican.com/article.cfm?id=d-waves-quantum-computer-courts-controversy

Scientists Confirm D-Wave's Computer Chips Compute Using Quantum Mechanics
http://spectrum.ieee.org/tech-talk/computing/hardware/scientists-confirm-dwave-computer-chips-compute-using-quantum-mechanics

Well, why all the fuss?

Back there in 2011 during my fourth semester, I was in Modern Physics II class. During the semester, the class started with some normal lectures and ended with a series of presentations on emerging issues in modern physics, including high-T_C superconductors, SQUIDs, semiconductor laser devices, future computing devices, and so on.
We were divided into teams of 2, then each team received a scientific journal article on a specific issue. Our assignment was to find other relevant sources, cram them all into a short presentation, and write a term paper on it (however, though it was a term paper, there was still a mid-term and final exam).
My team's share was titled "Quantum Computing with Molecules" [Gershenfeld & Chuang, Sci. Am. 278 (6), 66-71 (1998)]. It started with some information on quantum computing and the physics behind it (qubits, entanglement, and so on), then described their try on the implementation using NMR on ¹³C chloroform. They ended the report discussing several roadblocks ahead on this approach and quantum computers in general. Long story short, while they succeeded in their experiment, the main roadblock deals with scaling the quantum computer up to a usable commercial product, because the qubits are too fragile for even the slightest interference.

Yet today, just several years later, the dream of quantum computing becomes reality!

The discovery of practical quantum computing is somewhat very important to future technological advances, because today's miniaturization processes in silicon-based technology will soon hit the atomic limit of several nanometers, at which scale various quantum mechanical effects dramatically change the transport properties of matter.
On the other hand, the qubit (which is the basic unit of information in quantum computers, as opposed to the bit in conventional computers), thanks to the superposition principle, can hold more than two states at the same time, not just |0> and |1>. Furthermore, the quantum entanglement effect, in which the states of two or more qubits are related to each other even when they are distanced far apart, will effectively eliminate the need for "wires" to transmit qubits. Therefore, on a quantum computer, a single operation can process more than one input set, and information in qubits can be instantly relayed. Obviously these are two reasons why quantum computers will be degrees of magnitude faster than today's fastest computers.
Researchers around the world have endeavored in various methods to implement quantum computing, such as photonics (using photons, that is, light), spintronics (using electron spins), molecular computing (the NMR system above counts as one example), DNA computing (yes, they tried to use nucleotides and DNA strands), quantum dot systems, laser trap systems, and many others.
Now, this D-Wave device is said to be based on adiabatic quantum theory, and it utilizes arrays of Niobium superconducting loops cooled to 20 mK (thats a millikelvin -- a thousandths of a kelvin -- and for comparison, water freezes at 273.15 K). Well, I can't say much about this, but for sure, the theory in the realm of condensed matter physics, and the device is crafted with some sophisticated technology...

Though it seems that many people are still skeptic about it, personally I'm quite optimistic about this D-Wave stuff. However, with its current price tag at $10M, I suppose we still have to wait a little longer, maybe for about 10-15 years, before quantum computers would be available as affordable consumer products. Well, isn't it the same story with conventional computing? It was enormously expensive PDPs and VAXs before IBM and Apple stepped in with their respective PCs and Macs...

Oh, by the way, the news about NASA's quantum computer had already entered Indonesia since May 17 (at jpnn.com, liputan6.com, and tempo.co), as a quick Google query on "komputer kuantum NASA" reveals. But I guess not many people from the scientific community here really care...