Nah. Just find some good open source projects on Github to help out with. Post some projects of your own on there (doesn't matter if its an original idea, but code that you are proud of). Get into an algorithms book and work your way through it (should be easy with a Physics degree).
After all of that work, good places will take a chance on you; then show them they were right to do so.
One piece of advice: Even if you think your C++ and Python are beyond beginner, I would recommend going through a C++ book (http://www.amazon.com/Primer-Plus-Edition-Developers-Library...) and a good Python book, if you haven't already, just to really refine your style and be aware of how to use the STL properly. Standards and practices matter a lot when you're a good Software Engineer.
If you do all of that, you'll be better than 70% of the people calling themselves "Software Engineers".
FYI. I'm a Software Engineer and my degree was in Linguistics and Literature.
After all of that work, good places will take a chance on you; then show them they were right to do so.
One piece of advice: Even if you think your C++ and Python are beyond beginner, I would recommend going through a C++ book (http://www.amazon.com/Primer-Plus-Edition-Developers-Library...) and a good Python book, if you haven't already, just to really refine your style and be aware of how to use the STL properly. Standards and practices matter a lot when you're a good Software Engineer.
If you do all of that, you'll be better than 70% of the people calling themselves "Software Engineers".
FYI. I'm a Software Engineer and my degree was in Linguistics and Literature.