Germany 

Graduates who want to make the world a greener and more sustainable place should head to Germany. In 2002, Germany introduced a National Strategy for Sustainable Development, which included a pledge to cut carbon emissions in half by 2050. And to make sure they hit these ambitious targets, the German government set up a series of prestigious postgraduate scholarship and award schemes to attract the best students from all over the world.

Earlier this year, Moroccan researcher Karima El Azhar won the German Green Talents Award 2019 for her PhD research on developing new sustainable construction and insulation materials. Professor Christa Liedtke, a member of the Green Talents jury, said, "Climate impacts and protection do not stop at borders, but can only be addressed globally in research and development. [...] It is the future of the planet that is at stake -- that is why young interdisciplinary and highly motivated young scientists are of great importance for overcoming global challenges. Their generation is the future."

USA

Postgraduate students in the US are pushing the boundaries of the material world through their revolutionary and often mindbending research into physics. For example, researchers at Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed wearable depth sensor technology, which is set to have a profound impact on virtual reality and augmented reality technology, as well as the transport and defense industries. They based the multi-lens technology on the eye structure of jumping spiders, who have a super sense of depth perception that enables them to pounce on unsuspecting prey. 

What's more, physicists who dream of unlocking the mysteries of the universe have the amazing opportunity to study at colleges with close links to NASA. Graduate student Brendan O'Conner chose George Washington University in Washington DC for this very reason. He told SI News, "I chose GWU because of the proximity to NASA Goddard Space Flight Center, where I now am funded to work for my research/thesis project. I was interested in High Energy Astrophysics, and this department is focused on the topics I was looking to engage in."

Switzerland

Switzerland is a small country with a big presence on the global stage. As well as being a hub for finance and tech, the European nation is also home to the United Nations and the Red Cross. The CERN research facility lies just outside of Geneva, housing the world's most powerful particle accelerator. What's more, Switzerland is where you'll find one of the most iconic natural wonders of the modern -- the Alps mountain range. And the cities are just as impressive. Geneva and Zurich are famous for their historical architecture, high-end shopping districts, and Michelin-star restaurants.

Unsurprisingly, tourism is booming in Switzerland. And with ever more customers to satisfy and competition to fend off, the next generation of hospitality industry leaders are coming up with innovate new models to meet demand. Based in the city of Lucerne, The World Tourism Forum is a collaboration between government ministers, leading academic, and research students that address the challenges and potential of the tourism industry. During a recent innovation camp event, The World Tourism Forum selected six of the most innovative tourism start-ups, awarding each winner with a $20,000 investment. Among the winners was The Trip Boutique, an online booking platform started by two Brazilian students who moved to Switzerland in 2012 to study master's degrees.

Sweden

Scandinavian countries are among the most egalitarian societies in the world, so it's no wonder that Sweden is leading the way in the sharing economy. Also referred to as the 'peer-to-peer economy' or 'collaborative consumption', the sharing economy is structured around online platforms that allow people to share their homes, cars, boats, appliances, and even clothes with other people. Kes McCormick, the program coordinator for Sharing Cities Sweden, said, "Through trials in Stockholm, Gothenburg, Malmö, and Umeå, sharing services will be developed using digital platforms, while testing and evaluating opportunities and risks. [...] We need to shift from an economy based on ownership to an economy in which sharing gives us access to the things we need."

Although it is still very much in its infancy, many leading academics and sustainability researchers have high hopes for a sharing economy. Dr. Yuliya Voytenko Palga from the University of Lund writes, "Cities accumulate large pools of idling resources, items which people do not use regularly. [...] The sharing economy offers opportunities to use underutilized goods, save resources, reduce emissions, connect and empower people, and build social capital." However, as Dr. Palga continues, this new economy could harm established businesses and may lead to another form of social segregation where people only share within closed communities. But if the next generation of postgrad researchers can work on addressing such issues, then the sharing industry could become a genuinely global phenomenon capable of radically altering our personal and economic relationships. 

Japan

Japan has a long tradition of technological innovation, and its current crop of academic researchers are continuing the trend with their pioneering work in many fields, not least robotics. Visitors to Tokyo can interact with these creations at the Miraikan National Science Museum. The museum is home to ASIMO, a humanoid robot that can run, jump, talk, and perform everyday household tasks. Like many other robots at the museum, ASIMO is a prototype of further models that now operate as carers, teachers, and even servers. In fact, Tokyo has the world's first restaurant serviced entirely by friendly machines. You can also stay at the Henn Hotel in Maihama Tokyo Bay, a hotel where all the front of house staff are robots!

Japan is the world leader in new robotic fields, including smart machines that can perform complex medical procedures, provide additional security services, and even travel through space! Researchers from the University of Tokyo also helped design a set of disaster response robots, some of which were used to decontaminate the Fukushima Nuclear Power Plant after the 2011 earthquake and tsunami disaster. 

United Kingdom 

As the birthplace of the industrial revolution, the UK played a significant role in creating the modern world. Inventions like the steam engine and the spinning jenny (a spinning frame for weaving) changed the nature of work and industry forever, ramping up production and, in turn, consumption like never before. Today, we stand on the cusp of a new revolution. Powered by automation and AI machines, the next leap forward will usher in a new age where science-fiction may well become science fact. And once again, UK engineers and scientists are at the very forefront of change. 

A study by McGuire Research found the UK is one of the biggest investors in the technology of the future, such as artificial intelligence (AI). Of the British companies surveyed, 20% reported a yearly spend of over £40 million in AI, while 47% are investing between £12-£40m in AI every year. And with even more backing from big government spending, the UK's AI industry is on its way to a very bright future. Mark Jennings, the operations director for a large health firm with a big stake in AI, said, "Thanks to increased government funding for AI projects, a strong ability to scale AI investments, and a skilled workforce, the UK will continue to be a world leader in AI from which our economy will reap benefits in the coming years."

Much of the spending is going towards higher education programs to ensure the UK continues to produce highly-skilled graduates to power this new and exciting industry. This includes a £200 million project to create 16 AI centers based on campuses all across the country, with a goal of training 2,000 PhD students within the next five years. Each center will specialize in a particular area of AI, putting the UK -- and graduates from UK universities -- in an ideal position to succeed in this cutting-edge industry. 

So now you know some of the best places to study for your PhD, the world -- and academia -- is your oyster...