Quanten is not an English word
The word quantum has made it all the way from physics to areas such as movies and parcel services (knowing about the uncertainty principle of quantum mechanics, the name quantum view for a parcel tracking service causes some mild anxiety). The phrase quantum leap (Quantensprung in German) is commonly used, even though it typically refers to a large change or achievement whereas the scientific word quantum refers to the smallest possible unit of something.
Today’s post is about something else though, namely the mistake of saying the German word quanten instead of the English word quantum when speaking English. This mistake is often made by German speakers when using scientific expressions such as quantum mechanics, quantum Hall effect, or quantum Monte Carlo (follow these links if you want to learn some science). Most notably, I have witnessed a German Nobel Prize winner repeatedly saying
Quanten Hall Effect
Quantum Hall Effect,
with the word Quanten pronounced as if it were an English word.
A second pitfall is the pronunciation of quantum. Many German speakers pronounce it as [ˈkwʌntum], that is with the letters a and u pronounced as in German. The correct pronunciation is either [ˈkwɒntəm] (British English) or [ˈkwɑːntəm] (American English), listen here.
Two other words that often cause similar problems are superconductivity and superfluidity. Difficulties arise because in German the corresponding words are Supraleitung and Suprafluidität. As a result, you can quite often hear German native speakers mix up these terms when speaking English, which leads to word creations such as supraconductor or suprafluid. By the way, the words super and supra both go back to Latin and can loosely be translated as “above”.