A quantum computer harnesses some of the almost-mystical phenomena of quantum mechanics to deliver huge leaps forward in processing power. Quantum machines promise to outstrip even the most capable of todaysand tomorrowssupercomputers.
They wont wipe out conventional computers, though. Using a classical machine will still be the easiest and most economical solution for tackling most problems. But quantum computers promise to power exciting advances in various fields, from materials science to pharmaceuticals research. Companies are already experimenting with them to develop things like lighter and more powerful batteries for electric cars, and to help create novel drugs.
The secret to a quantum computers power lies in its ability to generate and manipulate quantum bits, or qubits.
Today’s computers use bitsa stream of electrical or optical pulses representing1s or0s. Everything from your tweets and e-mails to your iTunes songs and YouTube videos are essentially long strings of these binary digits.
Quantum computers, on the other hand, usequbits, whichare typically subatomic particles such as electrons or photons. Generating and managing qubits is a scientific and engineering challenge. Some companies, such as IBM, Google, and Rigetti Computing, use superconducting circuits cooled to temperatures colder than deep space. Others, like IonQ, trap individual atoms in electromagnetic fields on a silicon chip in ultra-high-vacuum chambers. In both cases, the goal is to isolate the qubits in a controlled quantum state.
Qubits have some quirky quantum properties that mean a connected group of them can provide way more processing power than the same number of binary bits. One of those properties is known as superposition and another is called entanglement.
Qubits can represent numerous possible combinations of 1and 0 at the same time. This ability to simultaneously be in multiple states is called superposition. To put qubits into superposition, researchers manipulate them using precision lasers or microwave beams.
Thanks to this counterintuitive phenomenon, a quantum computer with several qubits in superposition can crunch through a vast number of potential outcomes simultaneously. The final result of a calculation emerges only once the qubits are measured, which immediately causes their quantum state to collapse to either 1or 0.
Researchers can generate pairs of qubits that are entangled, which means the two members of a pair exist in a single quantum state. Changing the state of one of the qubits will instantaneously change the state of the other one in a predictable way. This happens even if they are separated by very long distances.
Nobody really knows quite how or why entanglement works. It even baffled Einstein, who famously described it as spooky action at a distance. But its key to the power of quantum computers. In a conventional computer, doubling the number of bits doubles its processing power. But thanks to entanglement, adding extra qubits to a quantum machine produces an exponential increase in its number-crunching ability.
Quantum computers harness entangled qubits in a kind of quantum daisy chain to work their magic. The machines ability to speed up calculations using specially designed quantum algorithms is why theres so much buzz about their potential.
Thats the good news. The bad news is that quantum machines are way more error-prone than classical computers because of decoherence.
The interaction of qubits with their environment in ways that cause their quantum behavior to decay and ultimately disappear is called decoherence. Their quantum state is extremely fragile. The slightest vibration or change in temperaturedisturbances known as noise in quantum-speakcan cause them to tumble out of superposition before their job has been properly done. Thats why researchers do their best to protect qubits from the outside world in those supercooled fridges and vacuum chambers.
But despite their efforts, noise still causes lots of errors to creep into calculations. Smart quantum algorithmscan compensate for some of these, and adding more qubits also helps. However, it will likely take thousands of standard qubits to create a single, highly reliable one, known as a logical qubit. This will sap a lot of a quantum computers computational capacity.
And theres the rub: so far, researchers havent been able to generate more than 128 standard qubits (see our qubit counter here). So were still many years away from getting quantum computers that will be broadly useful.
That hasnt dented pioneers hopes of being the first to demonstrate quantum supremacy.
Its the point at which a quantum computer can complete a mathematical calculation that is demonstrably beyond the reach of even the most powerful supercomputer.
Its still unclear exactly how many qubits will be needed to achieve this because researchers keep finding new algorithms to boost the performance of classical machines, and supercomputing hardware keeps getting better. But researchers and companies are working hard to claim the title, running testsagainst some of the worlds most powerful supercomputers.
Theres plenty of debate in the research world about just how significant achieving this milestone will be. Rather than wait for supremacy to be declared, companies are already starting to experiment with quantum computers made by companies like IBM, Rigetti, and D-Wave, a Canadian firm. Chinese firms like Alibaba are also offering access to quantum machines. Some businesses are buying quantum computers, while others are using ones made available through cloud computing services.
One of the most promising applications of quantum computers is for simulating the behavior of matterdown to the molecular level. Auto manufacturers like Volkswagen and Daimler are using quantum computers to simulate the chemical composition of electrical-vehicle batteries to help find new ways to improve their performance. And pharmaceutical companies are leveraging them to analyze and compare compounds that could lead to the creation of new drugs.
The machines are also great for optimization problems because they can crunch through vast numbers of potential solutions extremely fast. Airbus, for instance, is using them to help calculate the most fuel-efficient ascent and descent paths for aircraft. And Volkswagen has unveiled a service that calculates the optimal routes for buses and taxis in cities in order to minimize congestion. Some researchers also think the machines could be used to accelerate artificial intelligence.
It could take quite a few years for quantum computers to achieve their full potential. Universities and businesses working on them are facing a shortage of skilled researchersin the fieldand a lack of suppliersof some key components. But if these exotic new computing machines live up to their promise, they could transform entire industries and turbocharge global innovation.
Explainer: What is a quantum computer …
- Noisy Quantum Computers Could Be Good for Chemistry Problems ... - April 11th, 2019
- What is a Quantum Computer? - Definition from Techopedia - April 11th, 2019
- What Is a Quantum Computer? | JSTOR Daily - April 11th, 2019
- Measuring Quantum Computer Power With IBM Quantum Volume ... - April 9th, 2019
- What Can We Do with a Quantum Computer? | Institute for ... - March 7th, 2019
- Qubit - Wikipedia - February 25th, 2019
- Quantum computer | computer science | Britannica.com - January 10th, 2019
- IBMs new quantum computer is a symbol, not a breakthrough - January 9th, 2019
- IBM unveils the world's first quantum computer that ... - January 9th, 2019
- Were Close to a Universal Quantum Computer, Heres Where We're At - November 28th, 2018
- Schrdinger's Killer App: Race to Build the World's First ... - August 7th, 2018
- How Quantum Computers Work - May 3rd, 2018
- This is what a 50-qubit quantum computer looks like - January 15th, 2018
- Inside Microsofts quantum computing world | InfoWorld - January 1st, 2018
- Microsoft Takes Path Less Traveled to Build a Quantum ... - December 13th, 2017
- Researchers create new type of quantum computer | Harvard Gazette - December 12th, 2017
- Microsoft releases quantum computing development kit preview ... - December 12th, 2017
- Intel moves towards production quantum computing with new 17 ... - October 11th, 2017
- Quantum computer a possibility in 10 years - News.com.au - NEWS.com.au - September 7th, 2017
- Scientists Propose a New Kind of Quantum Computer, But What ... - Gizmodo - September 7th, 2017
- Quantum detectives in the hunt for the world's first quantum computer - Phys.Org - September 7th, 2017
- Scientists Just Found A Use For The Hashtag In Quantum Computing - Gizmodo Australia - September 4th, 2017
- The Future of AI: From Quantum Computing to the Internet of Things - Outer Places - September 4th, 2017
- We're About to Cross The 'Quantum Supremacy' Limit in Computing - ScienceAlert - September 2nd, 2017
- Explaining the Most Recent Record for Quantum Computing: A 51-Qubit Quantum Computer Array - All About Circuits - September 2nd, 2017
- USRA Upgrades D-Wave Quantum Computer to 2000 Qubits - insideHPC - September 1st, 2017
- Quantum encrypted box hints at unhackable communication - Wired.co.uk - September 1st, 2017
- Quantum Computer Programming: What You Need to Learn to Get ... - TrendinTech - September 1st, 2017
- Google's John Martinis Believes Quantum Computing Threat to Be Long Way Off - Bitcoin News (press release) - August 31st, 2017
- Australian quantum computing outfit goes commercial - Networks Asia - August 31st, 2017
- Elusive Majorana Particle Takes Major Step Towards Quantum Computing - IEEE Spectrum - August 29th, 2017
- Australia gets quantum computing company - ACS (registration) - August 28th, 2017
- Quantum Computing and Financial Trading - LeapRate - August 28th, 2017
- Russians Lead the Quantum Computer Race With 51-Qubit Machine - Edgy Labs (blog) - August 28th, 2017
- Bitcoin vs. The NSAs Quantum Computer Bitcoin Not Bombs - August 26th, 2017
- qBitcoin: A Way of Making Bitcoin Quantum-Computer Proof? - IEEE Spectrum - August 26th, 2017
- Hype and cash are muddying public understanding of quantum ... - Phys.Org - August 26th, 2017
- Silicon Quantum Computing launched to commercialise UNSW ... - ZDNet - August 23rd, 2017
- IEEE Approves Standards Project for Quantum Computing ... - Business Wire (press release) - August 23rd, 2017
- Introducing Australia's first quantum computing hardware company - CIO Australia - August 23rd, 2017
- What is quantum computer? - Definition from WhatIs.com - August 22nd, 2017
- Hype and cash are muddying public understanding of quantum computing - The Conversation AU - August 22nd, 2017
- Finns chill out quantum computers with qubit refrigerator to cut out errors - ZDNet - August 22nd, 2017
- UNSW joins with government and business to keep quantum computing technology in Australia - The Australian Financial Review - August 22nd, 2017
- 'Tools of DESTRUCTION' Quantum computers WILL wreak havoc ... - Express.co.uk - August 19th, 2017
- Quantum computing comes of age - Alphr - August 14th, 2017
- No, Quantum Teleportation Won't Let Us Send Instant Messages to Alpha Centauri - Air & Space Magazine - August 12th, 2017
- Google on track for quantum computer breakthrough by end of ... - August 11th, 2017
- Closing In On Quantum Computing | WIRED - August 11th, 2017
- World's Leading Physicist Says Quantum Computers Are Tools of Destruction, Not Creation - Futurism - August 10th, 2017
- Will you be able to trust a quantum computer? - Digital Journal - August 9th, 2017
- New Methods of Controlling Electrons Could be Major in Quantum Computing - TrendinTech - August 5th, 2017
- Exactly what could quantum computers do? - Electronics Weekly - August 4th, 2017
- What is quantum computing and why does the future of Earth depend on it? - Alphr - August 2nd, 2017
- The Age of Quantum Computers is upon us! - Gizbot - August 2nd, 2017
- Ultracold molecules hold promise for quantum computing | MIT News - MIT News - August 1st, 2017
- Clarifiying complex chemical processes with quantum computers - Phys.Org - August 1st, 2017
- When Will Quantum Computers Be Consumer Products? - Futurism - August 1st, 2017
- Quantum Computers Just Moved a Step Closer to Reality - NBCNews.com - August 1st, 2017
- A New Breakthrough in Quantum Computing is Set to Transform Our ... - Futurism - August 1st, 2017
- Quantum computers compete for supremacy - Salon - July 10th, 2017
- Quantum Computers Compete for "Supremacy" - Scientific American - July 5th, 2017
- Less is more for Canadian quantum computing researchers - ITworld - July 4th, 2017
- New method could enable more stable and scalable quantum ... - Phys.Org - July 4th, 2017
- Volkswagen buys D-Wave quantum computers which sell for $15 million each - Robotics and Automation News (press release) (registration) - July 2nd, 2017
- 6 Things Quantum Computers Will Be Incredibly Useful For - Singularity Hub - July 1st, 2017
- Quantum Machine Learning Computer Hybrids at the Center of New Start-Ups - TrendinTech - June 20th, 2017
- Israel Enters Quantum Computer Race, Placing Encryption at Ever-Greater Risk - Sputnik International - June 20th, 2017
- Prototype device enables photon-photon interactions at room ... - Phys.Org - June 20th, 2017
- The Quantum Computer Factory That's Taking on Google and IBM - WIRED - June 20th, 2017
- Toward optical quantum computing - MIT News - June 17th, 2017
- Get ahead in quantum computing AND attract Goldman Sachs - eFinancialCareers - June 16th, 2017
- KPN CISO details Quantum computing attack dangers - Mobile World Live - June 16th, 2017
- Quantum Computing Technologies markets will reach $10.7 billion by 2024 - PR Newswire (press release) - June 14th, 2017
- From the Abacus to Supercomputers to Quantum Computers - Duke Today - June 13th, 2017
- Quantum Computers Will Analyze Every Financial Model at Once - Singularity Hub - June 13th, 2017
- Are Enterprises Ready to Take a Quantum Leap? - IT Business Edge - June 13th, 2017
- Scientists May Have Found a Way to Combat Quantum Computer Blockchain Hacking - Futurism - June 13th, 2017
- Microsoft and Purdue work on scalable topological quantum computer - Next Big Future - June 13th, 2017
- Doped Diamonds Push Practical Quantum Computing Closer to Reality - Motherboard - June 3rd, 2017