Lei Xue, graduated from Hunan University, majoring in communication engineering. In 2015, he entered the State Key Laboratory of Regional Optical Fiber Communication Network and New Optical Communication System of Shanghai Jiaotong University, under the tutelage of Professor Yililin. During the master's and doctoral period, the main research directions were high-speed optical access network and short-distance optical interconnection. During the doctoral period, he went to the Royal Institute of Technology in Sweden for joint training and obtained double doctoral degrees at home and abroad. After graduating with a Ph.D., he worked in Huawei Shanghai Research Institute, engaged in the work related to the fusion of optical and wireless.

Kungfu is in peacetime, thick accumulation and thin hair

2015 lab bench

I don’t know if there is anyone like me who is about to graduate, but has not yet figured out what job he likes, but he feels that staying in school is quite free, so he will take another postgraduate entrance examination and give himself more time to think. After the postgraduate entrance examination, I successfully received the admission notice from Jiaotong University, and I was full of joy. I never thought that this life, which was originally only 2 and a half years, would last for more than 6 years. Next, I will share my experience in this process, hoping to inspire some younger brothers and sisters who are about to embark on the doctoral path.

In the summer vacation of 2015, due to the needs of the projects in the group, I came to Jiaotong University to report two months in advance with my suitcase. Because I don’t have any special scientific research experience as an undergraduate, the research topic is directly linked to the project. I don’t know if it is easy to publish articles at that time, thinking that I can do whatever I want to do as a small master. Thinking back now, if I didn’t have a clear interest at the beginning, would I be able to check the papers of the teachers in my research group when I graduated from undergraduate, and which direction has the most articles, so that I can roughly determine the strengths of the research group and avoid having to go independently when I first came Do a subject without any accumulation. Fortunately, I was lucky, and the direction of the assignment was more suitable.

In this horizontal project, my specific task is to assist Brother Ji to complete the delivery of the prototype of 100G-PON in the spring of next year. During the course of the project, many problems were encountered. Various devices in the system often had inexplicable problems, and the debugging results were inconsistent under the same conditions. Repeatedly removing optical fibers, changing devices, and finding problems, I felt that this was a metaphysics. In addition, due to the small scale of the research group, the equipment is often borrowed and can only be tested at night when no one is using it, so staying up all night is commonplace. During that time, I often felt that I was just a young master who had to work so hard, so when I was tired, my eyes were empty, my eyes were dull, and I collapsed. But the brother still took the trouble, not arrogant or impetuous, thoughtful, carefully analyzed and recorded the results. I think this is also the key reason why the brother was able to achieve fruitful results during the master's and doctoral periods.

After a year of struggle, the project was finally successfully delivered in March 2016, and a press conference was held at Jiaotong University, which directly affected the share price of FiberHome. In addition, we made an unexpected discovery during the course of the project. Based on this discovery, I published my first conference paper in the last semester of the second year of graduate school, and it was also rated as a post-deadline paper (extraordinarily admitted before the conference deadline) thesis). In the eyes of outsiders, the paper was published in the second year of research, and the progress was very fast, but I knew that there was a lot of luck in it. I just realized the existing ideas, and the thesis was basically rewritten by the master sister. So if you see that your classmates have published various papers, you must not doubt your ability. After all, everyone comes in at different times and opportunities. The important thing is that you have not wasted time and the topic is still advancing. It is normal for a master's degree in the second year, and a doctor's degree in the third and fourth grades.

Participate in academic conferences and communicate with peers

ACP2016 and joint training instructor

ACP2016 group photo with Professor Steven Chu

Due to the acceptance of conference papers, an oral report was required. In October, I went to Wuhan to participate in the Asian Optical Communications Conference. Unexpectedly, this participation unexpectedly changed my later choice. As a rookie who has just stepped into the scientific research circle, it is the first time to participate in an academic conference. I feel like Grandma Liu came to the Grand View Garden to watch the excitement. All the big names talked about their work fluently on the stage, and people in the audience rushed to ask questions and express their opinions. Although I really wanted to participate in it, I still couldn't understand anything. But I have to admit that I will enjoy this atmosphere a little bit, a gathering that only belongs to scientific researchers.

After all, I have done research for two years, so I am curious about what the names I often see in the papers look like, a bit like meeting the original author at an offline reading meeting. During the meeting, I ran to take photos with these people, feeling a little bit successful in star chasing, I really don’t know why I was so thick-skinned. By chance, I took a group photo with Teacher Chen Jiajia from the Swedish Royal Institute of Technology, just because my brother said that she is the most famous female professor in the field of optical communication. I found out later that Mr. Chen and Mr. Yi are very close, and that Jiaotong University and KTH have a joint project, so the two supervisors together contributed to the joint doctoral training. Since I could go abroad for exchange and wanted to broaden my horizons, I switched from a master's degree to a doctorate degree in April 2017.

Although my story is not very meaningful and has a lot of luck, but if you have a need to go abroad, you want to know the big cows in your field, want to know their views on your work, and whether there is any possibility of cooperation in the future, then participate Academic conferences are really great opportunities.

Open your horizons, you will have more possibilities

A group went to Los Angeles to participate in OFC2017

Fast forward to 2017. In the first half of the year, I participated in the American Optical Communications Conference OFC held in Los Angeles, USA and the European Optical Communications Conference ECOC held in Gothenburg, Europe. Then in the second half of the year, I went abroad and came to the Swedish Royal Institute of Technology to start a joint Ph.D. Cultivation, just arrived at the destination, and went to Spain and Greece to participate in the meeting of the EU project. This year basically didn’t stop much, I went to 5 different countries, saw the beautiful scenery that can only be seen in books and movies, met people of different skin colors, spoke different languages, and had different values , a different story. It turns out that the world is so big and you are so small. In fact, you can have more choices in life, not just doing crazy questions when you are approaching graduation, and finding a job.

Marie Curie project meeting

When I came to a foreign country, apart from adapting to the local lifestyle (cooking for myself and meeting new friends), the biggest change was the change of the scientific research model. When I was in the research group of Jiaotong University, I had to submit a weekly report to report the results every week. The progress of scientific research was basically pushed forward by the instructor. The teacher was the one who took the initiative. I just needed to complete what was required and when. However, the role of a foreign supervisor and a doctorate is like a peer relationship. You need to be responsible for your own work. When you actively seek help, you will provide resources and advice for you. Of course, this may be one-sided. Every supervisor has his own management style, and every student has his own research stage. I can only say that my state changed like this at that time. Although these two styles are not consistent, the core hope is to train students to be able to conduct scientific research independently. This process will have higher requirements for the ability to solve problems. If you can ask meaningful questions and solve them yourself , I feel that graduation is not far away.

SJTU graduation defense

Sweden graduation defense

From the beginning of graduate school, to transfer to Ph.D., and finally to the joint training abroad, these experiences were out of reach for me when I was an undergraduate. The time of more than six years is not short, and there are many difficulties in the middle, but looking back, I still feel very lucky that I made this choice at that time, which gave me the opportunity to see the outside world when I was supposed to enter the workplace, and had the opportunity to go deeper. Digging in a direction gives you the chance to meet different people. Although it took a long time, I have the confidence to tell my original self after I finally graduated, and I also want to say to every newcomer who has just entered the field of scientific research, you can actually make your dreams bigger, and you can be less when faced with choices. Weigh the pros and cons and listen to your inner voice. Here is also a song recommended by Wei Bo - Good Riddance, you can listen to it when you are confused and helpless.

Having said so much, it seems that there is nothing to do. Finally, I will give some suggestions on the problems that everyone will encounter during the doctoral period:

1. How to enter scientific research?

· Inherit the work of the brothers and sisters who have graduated in the same direction, familiarize themselves with their graduation thesis, clarify the research ideas, collect the questions that they don't understand, and concentrate on asking and solving them.
· Read the doctoral thesis of the same research group in the world to understand what issues the entire academic and industrial circles are paying attention to, and the reasons for their attention.
· Check out the international projects in the general direction, each project will have a public website, look at their project goals and difficulties, it may be helpful for you to determine your research direction.
· In addition to learning, output some content frequently: group meeting reports, simulations.

2. The tutor is too busy, and I don’t know what to do?

· Set some goals that can be quantified and implemented to make the work more fulfilling, for example: I will read 2 papers today, I will output 3 ideas this month, and I will publish 5 papers this year. Whichever is the best, can afford the middle.
· Record the problems you usually encounter (confusion is also a problem), and then take the initiative to report progress and solve these remaining problems in the weekly report. In addition, you can also communicate with your brothers and sisters and take the initiative.

3. Someone at the same level sent nature, but I haven't OC yet

· As I said before, put your mind right. The time to enter the research group is different, the topics are different, and the opportunities are different.
Compared with yourself, it is good to make progress every day.

4. The paper was rejected many times - what kind of rubbish paper is this?

· The thesis is revised, not written in one go, so don't be afraid to revise. Even if you feel that the writing is not good enough, don't submit it, your intuition is generally quite accurate.
· Pay more attention to other people's "routines" when reading papers, and then apply them more every time you write.

5. Poor oral English and dare not communicate

· It is not necessary to be able to communicate like the locals in daily life. It is mainly used in academic scenarios, making academic reports and answering questions.
· Record the content of the online international conference, listen to and retell the content of others many times, and understand the thinking of others' answers.
· Watching the American drama Modern Family is also good. It can practice listening and relieve stress.

6. Worried about delaying graduation

· It is necessary to set a good goal in normal times (you have to step up to achieve it, not like eating 3 bowls of rice a day), and graduation will not be so difficult.
Graduation is not the ultimate goal of life. Don’t always imagine that your life will become better after graduation. Difficulties always exist. The process of overcoming setbacks and difficulties is your life.