Google "Fluechtlingshilfe in Deutschland" to find Rechtsberatung as a first step. Given the circumstances, I personally think you qualify for that term. The problem with Germany since the war is that the country that used to be treated with Kollektivschuld for what happened under Hitler, now decided to turn around and treat Russians in Germany the same way (e.g., boycotting Russian owned businesses). Good luck.

Not directly related to your question, but probably relevant: You seem to be using your real name in your user profile. Just to be on the safe side I suggest to replace your name with a different user name. In case that you are required to go back to Russia (due to visa stuff or something - although I genuinely hope that you can stay in Germany), you might not want to have your name along with the first sentence of the question on the internet.

Regarding the question: I think it might improve the probability to get useful answers if you could add a bit of information: (1) What precisely is your degree in? Would you also consider options that are not directly related to quantum computing? (It seems likely that, due to the political situation, you were rejected due to dual use concerns, which might be more relevant in quantum computing than in other related fields.) (2) When you say you don't have enough time left, are you referring to visa issues, or to something else? [...]

[...] (3) Can you say whether your current main priority is that you can start a PhD (or related scientific work), or that you don't want to return to Russia currently? (Just to avoid misunderstandings: I would consider both priorities completely legitimate; but it might affect what kind of advice users here will be able to give you.) (4) How well do you know the people at the institution where you planned to do your PhD? (Depending on that, they might or might not be able and/or willing to help you in finding alternative opportunities.)

The problematic part, of course, is that (i) Germany's concerns about spies, information that is sensitive from a military perspective, etc, are all completely legitimate, and (ii) there is no right to obtain a visa of any kind anywhere in the world. Granting a visa is completely within the purview of the state, and that state does not generally have to explain its reasoning when denying a visa. It can also not be forced to reconsider.

Although it might not be fair to the individual, rules like this exist for valid reasons and at my institute, we cannot hire people from Iran, China and, due to recent developments, Russia. As the war with Ukraine changed things quite a lot, I it very possible that the view on hiring Russians has changed only recently (especially in "sensitive" topics), that could be the reason for other people from your university having been accepted in the past but now it's not possible anymore.

@WolfgangBangerth: Well, but the problem doesn't seem to be that OP was denied a visa; he was denied permission to work on a certain position. Re your last 1.5 sentences on visa decisions ("and the state...") : that doesn't apply to Germany, see here (unfortunately, I couldn't find it in English, although the site probably exists in English).

@Sursula-they- I would agree that rules are fair if I wanted pursue PhD rocket science or something really military, but quantum computing is very experimental thing and even before the war russian couldn't afford that kind of equipment that you could find in Germany simply because russian government doesn't care about science. Also, what if I am followed because of my political views? In such case I couldn't return back and am I still potential threat?

@EvgeniiGadylshin The problem is that it is next to impossible for a university employee to make any judgement towards your situation. Even a person willing to spy can say that they are persecuted by their government to increase their chances. I understand your frustation, but it is very likely that there is no satisfactory solution. On the flip side, we wanted to hire someone from Russia at our department and tried very hard, but in the end, it was not allowed by the higher instance.

Here the perspective of someone working at a university in Baden-Württemburg. It is now very hard for us to get permission to get people with Russian nationality. We mainly deal with the "higher-ups" in the university that says no. But what we hear is that the "higher-ups" get all kinds of contradictory and changing directives, and thus don't know what is or is not allowed. To be on the safe side, they often just say no. With the right kind of pressure from the inside, that can sometimes be changed. But for that you need insiders to argue your case and even than there is no guarantee.

As to Russians who were previously allowed to do what you want to do: Those who are in before the war in Ukraine can stay, but who knows what happens to them when their contract ends. The advantage they have, as that people inside know them and are thus more likely to be successful when arguing their case.

@MaartenBuis Recently I was told something like that, that all this measures is new and may be my case needed more time to be clear. Your comment gives at least a little bit of hope. Do you know cases where such problem was resolved? Is it useful to tell press about my situation? Germany was an attractive place for students from my university and my university more less known in the world(top 50 in physics), I think Germany and young researched could benefit greatly if they could be allowed to work there.

I am afraid only for some students who eventually got permission to start a masters program in sociology. I know there was a discussion about a PhD student. However, someone else took it upon himself to argue that students case, and I don't know what happened. At the time (about 3 months ago) it did not look good. Not impossible, but a very real chance that we would get rejected (at least in the short term).

The best press strategy would probably be if people from the German department you applied to went to the press. If that is not possilbe, try contacting people @gnometorule suggested. They know the local situation, and probably the journalists. That makes it easier to strike the right tone. They can give your details to the journalist so (s)he can do an interview with you to get a "human side" to that story.

However, some parents from Russian collegues of mine who have given interviews here in Germany have gotten none to subtle visits where they were told that their child should shut up. So whenever you go public, be aware that the Russian embasy is reading that to.

And to give more details, there is no blanket ban for certain nationalities, what might be required for some nationalities (Iran, Syria, Russia now) is that a security background be performed, which takes time and resources, and some institutes simply do not want to do it and prefer to go with another candidate that could be hired with the standard procedure (even if its a non-EU citizen). So what your question says is possibly your interpretation of what you were said by institute personnel, which might not tell the whole story.

And possibly security concerns can be many, it is always specific to you as a person. For example, maybe you have relatives working in the Russian Military or Defense Industry, or friends in the same situation. The (broad) institute where you will work could also do military or dual use research and there could be stricter security where you could not be allowed, or there would be too many suspicions that you could be blackmailed by the Russian Government to spy while you work in Germany (or else they hurt your family in Russia), etc. Too many variables that you are not considering.

FWIW, MIPT is now under sanctions so there are additional reasons for Germans to be wary. There is no great option out there, unfortunately - all that's left to you is pulling more strings and either pressing your case or finding workarounds. Think about people who can vouch for you - I know a bunch of fellow DGAP graduates scattered across Europe, but they don't know you, the times are hard and this all is of limited use. I can only sympathize with your situation, especially given you're likely facing conscription at home. You should be able to secure a visa to stay at least. Stay safe.

@Dr.Snoopy: Ah yes, you're right. I was in a hurry when I wrote this comment and didn't note that the link only refers to Schengen visas. At least the option to go to court seems to be similar for other visas, too, though - so, in a sense, the state can indeed be forced to reconsider their decision (of course this does not tells us anything about the chances of success, and in many cases it will probably be completely pointless to go to court about it).

@JochenGlueck Sure, but from the question I cannot infer if a visa or residence permit was denied, to me it seems the position offer was rescinded ("After 3 months I was rejected from the promising position. ") which is not the same thing as a residence permit being denied. I think we need more details to provide some help.

@Dr.Snoopy @ JochenGlueck I was granted d visa for 6 month. I was in Germany since 1st June and after 3 months of staying here was rejected.

@EvgeniiGadylshin: Thanks for your reply! Does this mean that you visa lasts until end of November, or will it end earlier?

@EvgeniiGadylshin So what exactly was rejected, your residence permit application? Or was your contract canceled/rescinded? Did you get official letters or emails with this decision?

@Dr.Snoopy contract. I didn't receive any documents or letters from BAFA, I only got the email from professor. @ JochenGlueck my visa will be valid until the end of October.

That leaves you without many options, if the Professor does not want to hire you, that is legal and you do not have clear ways to appeal like in a visa or residence permit application, unless you want to sue the institute (very unlikely), your best option would be to find another job or apply for asylum (also unlikely to be granted).

@Dr.Snoopy Asylum might not be the best option overall, but out of curiosity - why is it unlikely to be granted? Do authorities not consider the threat of persecution real enough until the person gets their conscription papers and faces criminal liability for avoiding the draft (and at that point can't move out of the country by legal means, either)?

@Lodinn No, it is because not every person in Russia is being drafted, from a legal point of view, how do you prove threat of persecution if you have not been drafted? From what I understand here, the OP was not living in Russia when the "partial" mobilisation started, and if he has no military experience, why expect to be drafted? Also in the EU in general there is no right to asylum for conscious objections to military service as far as I know. My point is that you always need to prove persecution by the state.

I'm quite surprised by this German attitude. I'd recommend going to another country, that is more welcoming to Russians. I know that Switzerland, the UK and Israel are welcoming to incoming Russian scientists, and all have excellent universities. And there are probably many other countries. I'd recommend going there.

@Dr.Snoopy I see, thank you. On this side of the border, every man within the age range expects to be drafted, military experience or not. Some manage to successfully dispute it though, but that hangs on their social capital. OP's odds here are admittedly not that terrible, but stories of at best being arrested for half a day as one of the better-case scenarios are not too uncommon. If I were in OP's shoes, I'd still try something else before returning to Russia. Since they don't have a strong network of their own yet, their advisor might be of help (but they also go through quite a lot...)

@Dilworth What attitude exactly? The OP is outside of Russia, got a German visa, and this could happen in any of the countries you mentioned. Generalizing to a whole country is not representative of the situation. There have been cases of Russian spies and security issues in Germany. Also consider the Ukrainian refugee population in Germany, there could be social conflicts too.

@Lodinn Yes I would recommend finding another job in Germany or another country, specially one where possibly security concerns are non existent.

One thing in general, once your visa expires, you could be deported, but I don't think they deport people to Russia (this requires cooperation with the Russian government), and also there are no flights from Germany to Russia, so you could be in some legal limbo where you have no visa or residence permit, but still live in Germany, so your best chance is to find employment to support yourself.

I would guess that quantum computing is a pretty sensitive topic at the moment, due to its relationship to potentially unbreakable encryption. That might be reason enough, and not limited to Germany. Encryption is usually viewed as a "munition", IIRC.

@Dr.Snoopy: Is it clear that OP will be allowed to work if his visa is not prolonged, even if he is not immediately sent back to Russia? German immigration law can sometimes be weird (although some things seem to have improved over time).

@OP I think it might really be worthwhile to get some legal advice on the matter (and probably to do so quickly if your visa expires at the end of October).

@Buffy At least it is a subject to export control laws, aye. As far as I can tell, OP's advisor is a very nice person I happen to know from my student years and they seem to be working on something not directly connected to encryption but, unfortunately, work in the same lab with people who do work on encryption. This is sadly a common thing to have bad associations in modern Russian science even if you work strictly on non-military non-dual-purpose projects.

No wonder people are unwilling to take such risks.

I'll add to my comment way up there the following: First, quantum computing must be considered sensitive technology due to its applications in (or against) cryptography. Whether or not Russia is interested in supporting research in this direction is a secondary consideration, and I think it is not unreasonable for Germany to decide that it doesn't want to support Russian nationals to develop such technology.

Second, sanctions are not based on personal considerations. While OP here may very well have sentiments against the current Russian government, sanctions are targeted both at those who currently support a government, and those who might change it. That's why so many Russian oligarchs have lost control of their yachts: If they get mad at the current government because of the loss of money, then good: That's what the sanctions were intended to do.

The same goes both ways, of course: Russia turning off gas deliveries to Western Europe hurts innocent bystanders. The goal of these sanctions is to turn the population in Western Europe against their governments and to force them to adopt policies that are less against Russia. In all of this, Russia has no animus towards individual Europeans. Likewise, the German government might not care personally about OP, but wants OP to complain to the Russian government about the loss of opportunities.

Personally, I have great sympathy for OP. (In parts because the university of Stuttgart is my hometown uni, and I think it'd be a great opportunity for them to learn and work there.)

@JochenGlueck No, non-EU citizens cannot work without a valid visa or residence permit, this is very strictly enforced at multiple levels and is not a good idea to even try. And I say this having experience with Germany's migration system. Also there is the issue of having no work contract...

@Dr.Snoopy: Thanks for your response! I suspected so. That's why I was a bit confused by your suggestion "I would recommend finding another job in Germany" in one of your comments above (so I asked for clarification).