Germany is grappling with a scientists' brain drain as many of the brightest academic minds are moving away, an expert panel warned in a report to Chancellor Angela Merkel on Wednesday.
"Germany is losing many of the best scientists through emigration," the government's commission of experts on innovation and research cautioned.
Some researchers return to Europe's top economy, but overall Germany is not attracting enough scientists of the same calibre as those who have gone abroad, the report said.
"In particular for the best, the German research system doesn't seem to be attractive enough at the moment," said the report by a panel of six university professors.
Between 1996 and 2011, more than 23,000 active scientists emigrated, while around 19,500 came to work in Germany.
German scientists make up the biggest group of foreign researchers in many countries, including the United States, Switzerland, Netherlands and Belgium, the report said.
To counter the trend, the experts advised the government to implement programmes to seduce back leading scientists.
They also called for Berlin to push on with setting up centres of excellence within the German university system.
And they invited German research institutes to step up their recruitment of foreign staff and to make every effort to keep them.
The report welcomed the fact that German spending on research and development is at around its target of three percent of gross domestic product.
But it noted that German companies were increasingly spending their research budgets overseas.
Between 2009 and 2011, German companies' research and development expenditure outside of Germany jumped by more than 15 percent a year, compared to a 5.7-percent increase in Germany.
The report also criticised Germany's system of providing support to renewable sources of energy which, it said, was a "failure" notably for triggering a sharp rise in costs.
Berlin is currently working on reforming the law which deals with subsidies for electricity production from renewable sources, financed by a surcharge on consumers.
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