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Students demo fibre on steroids

A team from Wits University in South Africa and HUST in China show that multi-dimensional quantum communications with twisted light is possible down fibre networks

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Picture: University of the Witwatersrand

A PhD student at Wits University, along with colleagues from Wits and Huazhang University of Science and Technology in Wuhan, China, have found a way to transfer data securely across optical fibre networks.

The team, led by Wits Professor Andrew Forbes, has demonstrated that multiple quantum patterns of twisted light can be transmitted across a conventional fibre link that, paradoxically, supports only one pattern. The research, published in Science Advances, opens up the way to securely transport data across fibre networks, using multiple dimensions of light. Combined with the qualities of entangled quantum light, this data transfer can also now be done in a highly secure manner, which was previously not possible.

“Our team showed that multiple patterns of light are accessible through conventional optical fibre that can only support a single pattern,” says Wits PhD student, Isaac Nape, one of the leading PhD students on the team. “We achieved this ‘quantum trick’ by engineering the entanglement of two photons. We sent the polarised photon down the fibre line and accessed many other patterns with the other photon.”

Entanglement is when a pair or group of particles (such as photons) interact in such a way that the quantum state of each of the particles cannot be described independently of the state of the others, even when the particles are separated by a large distance. In other words, qualities such as the handedness (like left or right) of the one entangled particle will directly affect its entangled counterpart.

In this case, the researchers manipulated the qualities of the photon on the inside of the fibre line, by changing the qualities of its entangled counterpart in free space.

“In essence, the research introduces the concept of communicating across legacy fibre networks with multi-dimensional entangled states, bringing together the benefits of existing quantum communication with polarised photons with that of high-dimension communication using patterns of light,” says Forbes.

In the last few decades, quantum entanglement has been extensively explored for a variety of quantum information protocols, notably making communication more secure through Quantum Key Distribution (QKD).

Using so-called “qubits” (2D quantum states) the information capacity is limited but it is easy to get such states across fibre links using polarisation as a degree of freedom for the encoding.

The spatial pattern of light is another degree of freedom that has the benefit of high-dimensional encoding. However, while you can use many patterns of light in communications, this requires custom fibre optical cable, so it is unsuitable to already existing networks. 

“Our team found a new way to balance these two extremes, by combining polarisation qubits with high-dimensional spatial modes to create multi-dimensional hybrid quantum states,” says Nape.

“The trick was to twist the one photon in polarisation and twist the other in pattern, forming ‘spirally light’ that is entangled in two degrees of freedom,” says Forbes. “Since the polarisation entangled photon has only one pattern, it could be sent down the long-distance single-mode fibre, while the twisted light photon could be measured without the fibre, accessing multi-dimensional twisted patterns in the free-space. These twists carry orbital angular momentum (or spin), a promising candidate for encoding information.”

The team demonstrated transfer of multi-dimensional entanglement states over 250 m of single-mode fibre, showing that an infinite number of two-dimensional subspaces could be realised. Each subspace could be used for sending information, or multiplexing information to multiple receivers.

“A consequence of this new approach is that multiple patterns of light can be used in the fibre, but two at a time. It is a compromise because you can still get to “infinity” but by adding 2+2+2 … rather than in just one step,” says Forbes. Importantly, high-dimensional states are unsuitable for transmission over conventional fibre networks, whereas this new approach allows legacy networks to be used.

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Alexa can now read all messages

For the first time, an Alexa skill is available that makes it possible to listen to any kind of message while driving

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For the first time, Alexa users can now hear all their messages and email read aloud.

Amazon’s Alexa has become a household name. The world’s most popular virtual assistant is getting smarter every day and now, with Amazon Echo Auto, it’s in cars too. 

“In today’s highly connected world, messaging in the form of emails, texts, Facebook Messenger, WhatsApp and work channels like Slack, are integral to our daily routine,” says Barrie Arnold, chief revenue officer at ping. “However, distracted driving is responsible for more than 25% of car crashes and thousands of preventable fatalities every year.” 

ping, a specialist in voice technology founded by Arnold and South African Garin Toren, has developed a new Alexa skill as a companion to its patented smartphone app, that enables any message type to be read aloud. Designed for safety, productivity and convenience, “pingloud” is the first skill of its kind for keeping users connected when they need a hand or an extra pair of eyes.

“The ping Alexa skill is specifically designed to help drivers stay off their phones while giving them exactly what they want – access to their messages.” says Toren, ping CEO. 

Opening up Alexa to developers has resulted in an explosion of new skills available either for free or for a fee that unlocks premium services or features. These tools magnify the usefulness of Alexa devices beyond common tasks like asking for the weather, playing music or requesting help on a homework assignment. According to App Annie, the most downloaded apps in 2019 were Facebook Messenger, Facebook’s main app and WhatsApp, highlighting the importance of messaging. 

“The ping Android app is available worldwide from the Google Pay Store, reading all messages out loud in 30 languages,” says Toren. “The iOS version is in global beta testing with the US launch coming very soon.” 

Once you’ve signed up for ping, it takes a few seconds to link with Alexa, enabling all messages and emails to be read aloud by a smart speaker or Echo Auto device. Simply say, “Hey Alexa, open pingloud.” ping links an account to a voice profile so unauthorised users with access to the same Alexa cannot ask for the authorised user’s messages.

All major message types are supported, including Texts/SMS, WhatsApp, Facebook Messenger, WeChat, Snapchat, Slack, Telegram, Twitter DM’s, Instagram, and all email types. Promotional and social emails are not read by default.

*For more information, visit www.pingloud.com

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Coronavirus to hit 5G

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Global 5G smartphone shipments are expected to reach 199 million units in 2020, after disruption caused by the coronavirus scare put a cap on sales forecasts, according to the latest research from Strategy Analytics.

Ken Hyers, Director at Strategy Analytics, said, “Global 5G smartphone shipments will grow more than tenfold from 19 million units in 2019 to 199 million in 2020. The 5G segment will be the fastest-growing part of the worldwide smartphone industry this year. Consumers want faster 5G smartphones to surf richer content, such as video or games. We forecast 5G penetration to rise from 1 percent of all smartphones shipped globally in 2019 to 15 percent of total in 2020.”

Ville-Petteri Ukonaho, Associate Director at Strategy Analytics, added, “China, United States, South Korea, Japan and Germany are by far the largest 5G smartphone markets this year. The big-five countries together will make up 9 in 10 of all 5G smartphones sold worldwide in 2020. However, other important regions, like India and Indonesia, are lagging way behind and will not be offering mass-market 5G for at least another year or two.”

Neil Mawston, Executive Director at Strategy Analytics, added, “The global 5G smartphone industry is growing quickly, but the ongoing coronavirus scare and subsequent economic slowdown will put a cap on overall 5G demand this year. The COVID-19 outbreak is currently restricting smartphone production in Asia, disrupting supply chains, and deterring consumers from visiting retail stores to buy new 5G devices in some parts of China. The first half of 2020 will be much weaker than expected for the 5G industry, but we expect a strong bounce-back in the second half of the year if the coronavirus spread is brought under control.”

Exhibit 1: Global 5G Smartphone Shipments Forecast in 2020 1

Global Smartphone Shipments (Millions of Units)20192020
5G19199
Rest of Market13941165
Total14131364
 
Global Smartphone Shipments (% of Total)20192020
5G1%15%
Rest of Market99%85%
Total100%100%

Source: Strategy Analytics

The full report, Global Handset Sales for 88 Countries & 19 Technologies, is published by the Strategy Analytics Emerging Device Technologies (EDT) service, details of which can be found here: https://tinyurl.com/wep83gc.

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